查询词典 numerical analysis

As important ways for numerical solutions of partial differential equations, spectral methods have been developed rapidly in the past several decades. They not only have been widely applied to numerical simulations in various fields such as physics, mechanics, aerology, oceanics etc, and their theories of numerical analysis also tend to perfect.

作为数值求解的一种手段，谱方法在近几十年得到了蓬勃的发展，它不仅被广泛运用于物理、力学、大气、海洋等领域的数值计算，而且它的数值分析理论也不断地趋于完善。

The proposed method has the merit that the numerical characteristics of stochastic temperature field response can be obtained by analyzing the random temperature field just in one time.3. Perturbed numerical algorithm of nonprobabilistic convex set theoretical models on the temperature fieldThe uncertain parameters of physical parameters and initial boundary conditions of heat conduction are described by the convex model. The perturbation formulas of the upper and lower bounds of temperature field response with unknown-but-bounded parameters are given via the combination of matrix perturbation theory and the convex set theory model.4. Numerical analysis for transient temperature field with interval parametersConsidering the uncertainties of the transient heat transfer, the physical parameters and initial boundary conditions are regarded as interval variables.

该方法具有只进行一次随机温度场分析便可以获得其响应的数字特征的优点。3、温度场的非概率凸集合理论模型的摄动数值解法将结构导热的物理参数、温度场的初始和边界条件等不确定性参数以凸模型加以描述，基于矩阵摄动理论和处理不确定问题的凸集合理论模型的结合，导出有界不确定参数瞬态温度场响应所在集合的上、下界摄动计算公式。4、具有区间参数的瞬态温度场数值分析考虑结构瞬态热传导问题的不确定性，将结构各物理参数和温度的初、边值条件均视为区间变量。

In this paper numerical analysis method is used to carry out buckling analysis and mode analysis of the vacuum transfer line.

本文采用数值分析的方法对减压转油线结构进行了屈曲分析和振动特性分析。

In mathematics, Chinese scholars have achieved important results in fields such as number theory, theorem-proving by computer, differential geometry, topology, complex analysis, probability and mathematical statistics, PDE, functional analysis, numerical analysis and control theory and so on.

在数学方面，据我所知，中国数学家在诸如数论、定理机器证明、微分几何、拓扑学、复分析、概率论与数理统计、偏微分方程、泛函分析、数值分析和控制论等领域里也都取得了具有国际水平的成果。

This book reviews the many areas of numerical analysis, including the configuration polynomial, finite difference, factorial polynomials, summation, Newton formula, operator and configuration polynomial, Cheung section, close polynomials, TaylM more item type, interpolation, numerical differentiation, numerical integration, and with the series, differential equations, differential equations, least squares polynomial approximation, minimax polynomial approximation, rational function approximation, triangular approximation, non-linear algebra, linear equations, linear programming, boundary value problems, MonteCarIo methods and so on.

本书综述了数值分析领域的诸多内容，包括配置多项式、有限差分、阶乘多项式、求和法、Newton公式、算子与配置多项式、祥条、密切多项式、TaylM多项式、插值、数值微分、数值积分、和与级数、差分方程、微分方程、最小二乘多项式逼近、极小化极大多项式逼近、有理函数逼近、三角逼近、非线性代数、线性方程组、线性规划、边值问题、MonteCarIo方法等内容。本书的特色主要表现在利用例题及大量详细的题解来透彻地阐明所述内容的内涵，同时附有大量的补充题以便读者进一步巩固和深化从书中获得的数值分析知识。

Meanwhile, this paper systematically summarized the present fractional-order control theory results distributed mostly in such aspects as continuous and discrete time domain analysis, approximated numerical analysis, common frequency domain analysis, plane locus method based on variable transposition, etc, and became an effective foundation of forming a complete control and system theory for fractional-order control systems.

同时，论文对当前国内外已有的分数阶控制理论成果进行了较为系统的整理，主要集中在连续和离散时间域分析、近似数值分析、一般复频域分析、基于变量变换的平面根轨迹分析等方面，具有综述性质，是建立一套完整的分数系统控制理论与系统理论的有效基石。

Impsons Integration: In numerical analysis, Simpson s rule is a method for numerical integration, the numerical approximation of definite integrals.

pecifically：：辛普森整合：数值分析中，辛普森法则是一种方法，数值积分，数值逼近定积分。具体来说

By the numerical analysis of the ultimate bearing capacity of two- and three-dimensional footing under combined loading mode, the results show that the effect of alteration of underground water lever on bearing capacity of three-dimensional foundation is more than on that of two-dimensional foundation, the effect of soil gravity on bearing capacity of three-dimensional foundation is more than that of two-dimensional foundation. At the same time, the numerical calculation process of ABAQUS indicates that whether the geostatic stress is balanced or not has great effect on the numerical convergence. In view of the effect extent of dilation angle of soil on the ultimate bearing capacity and the failure pattern of foundation, the condition of two-dimensional plane strain is higher than that of the three-dimensional foundation.

复合加载模式下，通过对三维矩形基础和二维条形基础进行数值分析，结果表明：黏性土地基中地下水位的变化，对三维矩形基础极限承载力的影响程度高于对二维条形基础的影响；在求解地基极限承载力的过程中，土体重度对三维矩形基础的影响明显高于对二维条形基础的影响，同时ABAQUS数值计算过程表明，地基土体地应力能否合理平衡，对数值求解过程中是否收敛有很大的影响；就土体剪胀角对地基极限承载力的影响程度而言，二维平面应变情况下土体剪胀角对极限承载力的影响比三维情况下的影响更明显，即土体剪胀角对条形基础极限承载力的影响高于三维矩形基础。

The results of numerical analysis show that the elastic modular and the poisson ratio have no effect on two-dimensional bearing capacity, but can affect the ultimate bearing capacity of three-dimensional foundations and control the convergence and precision of finite element calculation; the earth pressure coefficient controls the geostatic stress of foundation, sequentially affects the ultimate bearing capacity of foundations and the convergence of numerical calculation. When calculating the ultimate bearing capacity of undrained saturated foundation, the complete formulation exists shear locking, and reduce formulation exists hourglassing, so the hybrid formulation is suitable to imitate the geomaterial. When the soil obeys nonrelevent flow rule, the yielding function is different from potential function, and the elastic-plastic matrix of soil is asymmetric, so the unsymmetry numerical solver and appropriate finite element mesh is required.

研究结果表明，土体弹性模量和泊松比对二维基础极限承载力没有影响，但是影响着三维矩形基础的极限承载力，控制着ABAQUS数值算法的计算精度与收敛速度；地基土压力系数控制着地基土体中的地应力平衡，从而影响着二维条形基础和三维矩形基础的极限承载力和地基破坏包络面；对于不排水饱和软黏土地基，常规的完全积分单元会造成剪力自锁现象，而减缩积分单元则存在过于柔化的现象，故采用杂交单元来模拟较合适；当土体服从非关联流动法则时，屈服函数与塑性势函数之间存在差异，从而导致土体弹塑性矩阵呈现非对称性，在有限元计算中必须采用非对称数值解法，并且合理地划分单元才能对极限承载力进行准确求解。

As to the short-span suspension bridge in little span, the numerical analysis method may be used for construction control calculation simply, and precision of calculation by numerical analysis method correspond to it by the finite element theory, meeting the demand of the construction control.

对于小跨径悬索桥，可以将计算简便的解析法用于悬索桥施工控制计算，而计算结果精度与有限位移法求出的结果相当，满足施工控制要求。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。