守恒

Based on the Navier-Stokes equations in conservative form derived with respect to nonorthogonal curvilinear coordinates and nonorthogonal velocity components, the numerical method for solving 3D viscous flow has been discussed.

本文基于非正交曲线坐标与相应的非正交速度分量下导得的守恒型N—S方程，讨论了求解三维粘性流动的数值方法，计算中显式时间推进算法与Baldwin—Lomax湍流模型被采用，应用本工作发展的程序，作为算例计算了一个沿径向非等截面环形叶栅的三维粘性流场，得到了诸如三维压力分布，总压损失分布以及十分清晰的二次流动图景等丰富的流场信息。

A three- dimensional turbulence model in non-orthogonal curvilinear coordinates is proposed to investigate the impacts of vegetation on channel morphology. The model includes vegetation-induced drag force and vegetation density in the control equations to describe the effects of vegetation on flow structure, and solves sediment continuity equation to compute channel geometry.

本文建立曲线坐标系下的三维湍流模型研究水生植物对河道形态的影响，在水流控制方程中加入植物阻力项和植物密度项来描述水生植物对水动力特性的贡献，通过泥沙质量守恒方程求解河道变形，在适体网格中求解模型的控制方程。

An optical system with refraction and total internal reflection was proposed according to the luminous characteristic of LED and the law of energy conservation. The ordinary differential equations satisfying the spots on the contour curve of TIR refractive and reflective planes were established. The coordinates of points on profile curves were obtained by solving these ordinary differential equations using Runge-Kutta method. The profile curves were acquired by curve fitting of the coordinate spots with software UG, and then TIR model of the projector and data of the surface shape suitable for NC manufacture were obtained.

根据LED的发光特性以及能量守恒定律选择采用折射全反射光学系统，通过建立TIR折射面及全反射面轮廓曲线上的点所满足的常微分方程，利用RungeKutta求解常微分方程得到轮廓曲线上点的坐标，再在UG中对坐标点进行曲线拟合得到轮廓曲线，进而得到TIR模型及适合数控加工的面形数据。

According to the kinetics of decarburization reactionand the theory of mass conservation,the mathematical model of RH decarburizationprocess has been established.

根据脱碳反应动力学和质量守恒原理建立了RH-MFB 脱碳数学模型。

And/or we advanced formulized definition about concept of conservation of information, and information essence definiens: information is a set of mark of attribute of thing.

及我们提出的"信息守恒"概念与公式化的定义，与"信息是事物及其属性标识的集合"的信息实质定义。

Moreover, Democritus argued that the quantity of matter is always constant, leading to proposals for both the indestructibility of matter and its conservation.

另外，他还提出，物质的数量总是恒定不变的，所以产生了物质永不灭和物质守恒的说法。

Conservation and derivation of the mathematical model.

数学模型的引出和守恒。

Two integral equations are derived from the equation of conservation of current.

从电流守恒条件出发，得到了两个积分方程。

Derived from energy equation and R.

从能量守恒的角度，运用R。

A vivid example of this: in the two deuterium nuclei polymerization into a helium-4 nucleus, it seems quality is not conservation, is the quality of helium-4 nucleus does not mean that two of the deuteron and quality.

这个例子生动地说明：在2个氘原子核聚合成1个氦4原子核时，似乎质量并不守恒，也就是氦4原子核的质量并不等于2个氘核质量之和。

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