数学模型

This paper shows the mathematic models and the calculation methods of the transient simulation in port equation form with full consideration of the periodic part and the nonperiodic part of the short circuit current and put the transformer, transmission line and the infinite power source in consideration. In resistance style fault it has perfect flexibility.

本文在充分考虑到短路电流的周期分量、非周期分量及带有变压器、线路和无穷大电源的情况下，给出了端口方程方法的机网暂态仿真研究数学模型和求解方法，结合电阻型故障模型，使故障仿真具有很强的灵活性。

According to fully implicit method, seepage model of low-permeability fractured gas reservoirs are discretized with finite difference method, and corresponding numerical model, coefficient matrix and matrix element are obtained; then based on modern software engineering, numerical simulation software was correspondingly developed with Fortran95 programming language

按照全隐式离散化方法，采用有限差分方法对低渗裂缝性气藏渗流数学模型进行了离散，得到了相应的数值模型、系数矩阵和矩阵元素。然后基于现代软件工程的基本思想，用Fortran95语言开发了相应的数值模拟软件

First, a universal mathematic model for AC servo system is established based on the study of servo drive system of high precision numerical controlled working table, then a method for simplifying the model is proposed.

在对高精密数控工作台的伺服驱动系统研究的基础上，建立了交流进给伺服系统的通用数学模型，并且研究了系统模型降阶简化的方法。

Finally, the validity and feasibility of the model were proved by its application on consignment case of a company.

最后给出了该数学模型在代销实例中的应用，并结合某企业分销案例证明了模型的正确性和可行性。

A general steady-state simulation model was presented for predicting the performance of air source heat pump unit in low ambient operating conditions.

为解决空气源热泵机组运行工况变化时，优化设计与性能预测等问题，建立了机组4个主要部件的稳态仿真数学模型，其中压缩机采用基于BP算法的人工神经网络方法，换热器采用分区集中参数方法建模，同时给出换热器中的换热关联式模型以及系统仿真流程。

Also, a method of quasi-stable adjustment and a software system researched and explored by Visual BASIC Language have been used to process the observation data of GPS dam deformation monitoring network..3 A mathematical model of three-dimension combined adjustment with GPS and other surveying data under station orthogonal coordinate system in deformation monitoring networks, has been brought forward.

提出了站心地平坐标系下GPS观测数据与其它地面测量数据三维变形监测网联合平差的数学模型，在数据处理模型中通过参数化的方法消除或减弱垂差和垂直折光的系统误差的影响。

Based on depth averaged mathematic model of flow and pollutant tr ans portation in non orthogonal curvilinear coordinates , the k-ε double equat ions' turbulence model and the coupling arithmetic of velocity water depth are a dopted, which are applied to the numerical simulation of the flow and the contam ination diffusion transportation.

基于非正交曲线坐标下水流与污染物扩散输移的深度平均数学模型，采用k -ε双方程湍流模型和速度—水深耦合算法，应用于实验室连续弯道的水流及污染物扩散输移的数值模拟，分别计算了流场及岸边和中心污染物排放的浓度场，得到与实测值吻合良好的计算

The material job and main conclusion are as follows:(1) A simple boundary orthogonalization procedure independence grids generation method is put forward on the base of algebraic grid generation method; Data structure and computational model on interface are established aiming at blocks of structured grids.

本文针对粘流场数值模拟技术的研究现状和发展动态作了比较全面的回顾与展望，重点研究了网格生成技术、数值求解技术、湍流模型技术和动边界模拟技术，在此基础上建立了模拟自由面湍流场的数学模型，并成功地应用到二维溢流坝和带闸墩的三维溢流坝过坝水流的数值计算。

On the basic of above job a mathematical model of simulation turbulent flow with free surface is established and triumphantly applied to numerical computation on 2D spillway and 3D spillway with frusta of brake.The material job and main conclusion are as follows:(1)A simple boundary orthogonalization procedure independence grids generation method is put forward on the base of algebraic grid generation method; Data structure and computational model on interface are established aiming at blocks of structured grids.

本文针对粘流场数值模拟技术的研究现状和发展动态作了比较全面的回顾与展望，重点研究了网格生成技术、数值求解技术、湍流模型技术和动边界模拟技术，在此基础上建立了模拟自由面湍流场的数学模型，并成功地应用到二维溢流坝和带闸墩的三维溢流坝过坝水流的数值计算。

By taking coordinated policies on some issues, such as supplement of inventory, treatment of out-of-stock and relationship among members of distribution system, a mathematical model to maximize total expected system profit is developed.

对分销中心库存的补充订货、缺货处理以及分销系统各成员之间的关系等问题采取协同策略，建立了使分销系统期望总收益最大化的数学模型，在分析模型解的存在性的基础上，探索了相应的求解方法。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷