查询词典 implicit

Finite element discretization was carried out on the mathematical model to get a fully coupled finite element equation with the parameters of element nodal displacement and element nodal pore pressure as unknown variables. Finally, the transient nonlinear finite element equation in incremental form for reservoir fluid-solid coupling is obtained by means of time discretization in implicit difference scheme.

基于与微分方程等价的加权余量公式，在空间域采用有限元离散，对时间域进行隐式差分格式离散，导出了以单元节点位移和单元节点孔隙压力为未知量的储层流固耦合的非线性有限元增量方程。

Firstly, the fully discrete standard finite element Galerkin method and the nonlinear finite element Galerkin method and the modified finite element Galerkin method in which time is discretized by the Euler implicit difference scheme are considered, and the - and - global relative errors and CPU time corresponding to the SG method, the NG method and the MNG method are computed respectively.

首先，对于全离散(时间离散是欧拉显式格式)标准有限元Galerkin方法和非线性有限元Galerkin方法以及修正有限元非线性Galerkin方法，分别进行数值计算，并比较了三种算法的计算解与精确解的误差估计及所耗费的CPU时间，结果验证了MNG方法要优于NG方法，而NG方法又优于SG方法。

In the paper, river and the downstream area of dike are regarded as a whole system, and hydraulic model of coupling 1-D river and gradual dike-break is established, therein the Preissmann implicit difference scheme is applied to Main River, and the FVM is applied to the breach and polder. On the basis of FVM and unstructured grids, TVD ?

本文将河道与堤坝下游区域视为一个整体，对于单一河道采用Preissmann四点隐式差分格式计算，对于溃口及圩区采用有限体积法，建立了一维河道与堤坝渐溃耦联的水力模型，也是一维、二维耦合的水流模型。

Starting with the basic concept about particle transport and the universal form of transport equation, the discuss is concentrated upon the transport equation and the implicit difference scheme under 3-D Cartesian coordinate, as well as the transport equation and the discontinuous finite element scheme under 2-D cylindrical geometry.

从粒子输运的基本概念和输运方程的一般形式入手，重点讨论了三维直角坐标中子输运方程和隐式差分格式，以及二维柱坐标中子输运方程和间断有限元格式。

In this paper, a high order accuracy difference method is presented for solving unsteady convection diffusion equation by using Implicit Perturbation Finite Difference scheme. Firstly, we use the steady convection diffusion equation, the constant coefficients of this equation are expanded to power series of grid-spacings, then the high-order Perturbation Finite Difference scheme is obtained by determining the coefficients of the power series. Put this scheme on unsteady convection diffusion equations and modified it, the IPFD scheme is constructed.

本文利用摄动差分思想，对定常对流扩散方程中的空间微商系数进行摄动展开，展开幂级数系数通过消去摄动格式修正微分方程的截断误差项求出，由此获得方程的隐式摄动差分格式，将此方法应用于非定常对流扩散方程，并加以修正，得到该方程的修正隐式摄动差分格式。

CO_2 Miscible Flooding ; Multicomponent ; Multiphase ; Unu-isothermal ; Numerical Simulation ; Implicit difference scheme ; Finite element method ; Optimal design ; Economic Evaluation

吉林大学；计有权 CO_2混相驱；多组分；多相；非等温状态；数学模拟；隐格式差分；有限元；优化设计；经济评价

An implicit differential method for the wave equation of rod pumping system［J］.

有杆抽油系统预测模型的隐式差分法［J］。

At first, for nonlinear assembly function, the implicit differentiation and multi-variables Tayler Series Expansion are used to obtain the linear relationship between input and output.

2三维偏差模型的线性化求解方法传统的蒙特卡洛仿真计算效率低，难以应用于复杂车身装配公差设计这样需求大量迭代运算的场合，本文提出一种高效率的线性化求解方法。

Automatic differentiation and implicit function differentiation rule were used to calculate the precise absolute and relative sensitivity coefficients, with no truncation error introduced.

提出一种基于自动微分和隐函数求导法则的精馏塔优化计算灵敏度分析方法，可以求出精确的、无截断误差的灵敏度系数，以反映精馏塔模型中各种不确定因素变化所引起的改变和影响。

Keywords distillation column semi-open equation model;automatic differentiation;sensitivity analysis;implicit function differentiation rule

精馏塔半开放模型；自动微分；灵敏度分析；隐函数求导法则

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