数学模型

The segregation of the binary granular mixture in Brazil nut problem was simulated by using discrete element model. The influences of the frequency and the amplitude of the vibration on the segregation are discussed.

采用离散单元模型对巴西果问题进行了模拟研究，采用本数学模型可以准确地预测出垂直机械振动导致的不同大小颗粒的分离现象。

This paper starts with the Naroll-Bertalanffy's hypothesis of the allometric growth of urban-rural population, namely and Sherratt's model about the distribution of urban population density, which are both based on the Christaller-l o ··sch's central place hypothesis and the hypothesis of supposing the regional population movement on the ideal land surface is similar to Brownian movement process.

基于中心地假设，从城市人口分布的Sherratt模型和Naroll Bertalanffy的城乡人口异速生长关系出发导出关于人口分布空间动力学和城市扩展时空过程的数学模型，然后借助Batty等关于城市生长的DLA -DBM模拟结果证明人口的区位选择过程与城市的分形形态存在着内在关系。

We have developed a three dimensional (3D) compositional mathematical model for two phase flow and derived a new 3D streamline model with capillarity and gravity effects.

在建立起可动凝胶深部调驱的油水两相多组分数学模型的基础上，推导出了考虑重力和毛管力的三维流线模型，将求解饱和度的三维问题转化为一维问题。

The according mathematics model and formula of characteristic value and inherent frequency were inferred and established.

固有频率的计算公式，并用实际算例对力学模型的合理性和数学模型的正确性进行了验

According to conservation of mass, this article establishes a kind of mathematical model for the equation equilibrium of chemical reaction, and also gives its solution both by man and by computer.

本文根据质量守恒定律建立了一种配平化学反应方程式的数学模型，并给出了模型的人工解法和计算机解法。

According to conservation of Mmass,the article establishes a mathematical model for the equation equilibrium of chemical reaction,and gives its solution both by man and by computer.

本文根据质量守恒定律建立了配平化学反应方程式的数学模型，并给出了模型的人工解法和计算机解法。

For confirming the method's efficiency, the turn-off transient mathematical model based on the chopper circuit is developed according to the proposed mathematic model of the turn-off transient current through IGCT, in which the RC-snubbers of IGCT, the stray inductance of chopper circuit and DC-link choke are taken into accounts.

该文建立基于斩波电路的IGCT关断暂态特性的数学模型。该模型充分考虑IGCT阻容吸收回路、线路杂散电感及限流电抗器对IGCT关断暂态过电压的影响。

Based on Chen's model about axial flow induced vibration of a rod bundle in an unbounded domain, a mathematical model concemed with circular domain is presented, and the expressions for fluid forces are given in detail.

三、基于Chen关于无界域轴向流动中棒束流致振动的模型，推导了有界域棒束轴向流致振动的数学模型，得到了关于流体力的表达式。

On the basis of the results, a mathematical model is developed to explain coalescence growth process of UFMP.

在此基础上建立了团聚生长数学模型，该模型能较好解释超微粉的团聚生长过程。

A set of physical model tests were made here and a calculation method considering resistance coefficient of pile group was applied in the numerical simulation of piled wharf through analysis and research.

因此，本研究采用局部物理模型试验，通过分析研究，提出在桩式码头数学模型计算中，考虑阻力系数的计算方法。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。