查询词典 numerical algorithm

The control volume integration was applied to deduce the discrete expressions of the convection-diffusion equations. The staggered grid and SIMPLE algorithm were introduced to deal with coupling between pressure and velocity, and then the numerical computation expressions of such variables as fluid flow velocity and pressure were deduced. Using the backward difference method and incremental theory to discretize the governing equations for fields of chemical reaction, material structure and chemorheology, the numerical computation expressions of variables such as the monomer conversion, average molecular weight and fluid viscosity were constructed.

应用控制容积积分法导出了对流—扩散方程的离散表达式，引入交错网格技术与SIMPLE算法，实现了耦合的压力场与速度场的分离式求解，推导得到了流体的流动速度、压力等物理量的数值计算式；采用向后差分方法和增量方法，实现了化学反应场、材料结构场、化学流变场控制方程的离散，获得了反应转化率、聚合物平均相对分子质量、流体黏度等物理量的数值计算式。

The numerical simulation of the detection signal was implemented with the theory of diffraction optics, and the numerical simulation of the wavefront reconstruction was realized with Green function algorithm under Neumann boundary conditions.

根据衍射光学理论，对其探测信号进行数值模拟，并利用Neumann边界条件的Green函数法对其波前重构进行数值模拟。

I wrote it myself numerical analysis courses designed algorithm, which is part of the numerical fitting.

我自己写的数值分析课程设计的算法，这里是数值拟合的部分。

Based on the numerical simulation algorithm in this paper, numerical results for temperature field are given and analyzed.

基于我们构造的三维温度场数值模拟算法，给出了变压器运行过程中温度场在空间与时间分布的数值结果，并对所得到的数值结果进行了分析。

Theoretical analysis and numerical results show that the new reconstruction algorithm can reduce the computational complexity and greatly improve the numerical stability.

理论分析和数值试验都表明，这种新的重建算法较常用的Newton-Raphson类算法，不仅数值稳定性有较大的提高，而且计算量有所减少。

This paper considers the pricing model of options under illiquidity. A new numerical procedure for solving the nonlinear parabolic partial differential equation is explored and the Thomas algorithm is used to improving the efficiency of the numerical scheme.

本篇论文提出一个在市场流动性不足情况发生时的选择权订价模型，并且发展一个新的数值方法来求解一个非线性抛物线型态的偏微分方程式，同时利用汤马斯演算法来提升数值运算的效率。

Shule River project area is located in northwest China\'s Gansu province,Hexi Corridor,which is the largest agricultural crop production base of Gansu province and typically arid and semi-arid areas. There are characteristics such as scarce rainfall,the temporal and spatial distribution inequality,strong evaporation,fragile ecological environment,the limited quantity of surface water. Agriculture,the people\'s living and ecological environment are significantly dependent on the groundwater. Based on the collection and processing of regional hydrological and geological data and the groundwater monitoring data,using the numerical simulation,geostatistics theory and multi-objective evolutionary algorithm,this paper studied the monitoring and evaluation of groundwater resources from the three aspects: groundwater numerical simulation and prediction,groundwater spatial variability and distribution and optimization modeling and sloving of groundwater monitoring network. The main work and research lies:(1) Using Yumen-Tashi basin,Anxi-Dunhuang basin and Huahai basin as study area,this paper used modflow model to simulate groundwater flow of three areas.

本文在收集和整理项目区水文地质数据以及地下水监测数据的基础上，基于数值模拟、地统计学理论及多目标进化算法，从地下水数值模拟与预测、地下水空间变异与分布特征分析以及地下水监测网优化建模与求解三个方面展开了对项目区地下水资源监测与评价的研究，主要研究工作如下：(1)以项目区内的玉门-踏实盆地、安西-敦煌盆地和花海盆地为研究区域，在《河西走廊项目中期计划调整报告》规划条件下，基于modflow模型对地下水水流进行数值模拟，计算并生成了三个区域2007-2030年地下水埋深预测数据以及等值图。

The key elements and techniques of the numerical wind tunnel are studied and analyzed.The basic idea of CFD is expatiated and the whole working process is presented.Discrete methods of the control equations based on the finite volume method and the PISO algorithm about the fluid numerical computation are researched also.

对基于CFD的数值风洞关键基础和技术进行研究分析，阐述了CFD的基本思想，研究了基于有限体积法的控制方程的离散方法以及流场的数值求解的PISO算法。

The main works of this paper are as follows.First, according to the three-step method, 1-D unsteady flow model in river network is introduced. A new topological structure is presented to describe and store the topology information and data in river network ,which realises the connection between GIS and the numerical program of hydraulic calculating and turns the program into a universal one .A new formula of internal boundary conditions with double-recursion algorithm is deduced, and the relationship of recursive coefficient between imaginary channel length and non-imaginary channel length is presented ,which makes sure that the model can comprise the numerical simulation of the internal boundaries such as side pipe outflow ,barrage, slice gate and drainage pump station.

主要工作如下：(1)根据三级解法建立了一维河网非恒定流模型，并提出了一种新的数据结构来描述和储存河网拓扑信息，方便了GIS平台和数值计算程序的衔接，实现了三级解法程序的通用性；从河段方程组出发，根据虚设河段法推导出了内边界条件的双追赶法公式，指明了虚设河段的追赶系数和非虚设河段追赶系数的关系，从而使模型可以模拟集中旁侧入流、堰、闸、水泵等内边界对行洪过程的影响。

In this paper we propose a new image reconstruction algorithm for electrical impedance tomography-Quasi-Newton algorithm, based on modified Bk. Numerical tests were made to verify the effectiveness of this algorithm.

摘 要 本文提出了一种新的电阻抗成像图像重建算法—基于修正Bk的拟Newton类算法，并通过数值试验验证了该算法的有效性。

Chrysanthemum of 10 thousand birthday is lax to edaphic requirement, with the arenaceous qualitative loam with fecund, good drainage had better.

万寿菊对土壤要求不严，以肥沃。排水良好的砂质壤土为好。

He unstepped the mast and furled the sail and tied it.

他拔下桅杆，把帆卷起，系住。