条件表达式

An explicit analytical solution of the threshold pump power of the laser has been derived based on rate equations which contain the attenuation coefficients of the pump and laser radiations as well as the major contribution of the re-emission of the upper level atoms to the pump wave by using the analytical solutions. An analytical solution of the minimum fiber length required for the onset of the oscillation is presented. In addition, the analytical solutions describing the variations of the density of the pump radiation and upper laser level population along the fiber length have also been given.

从速率方程组出发，在不忽略光纤损耗系数和保留再发射项主导部分的近似条件下推导出了双包层光纤激光器阈值泵浦功率的显函数解析表达式，得到了光纤激光器产生振荡所需的最小光纤长度的显函数解析解；还给出了泵浦光子数密度和上能级粒子数密度沿光纤方向随光纤长度变化的显函数解析解。

The transmitter updates the modulation mode, chooses the optimal transmission vector adaptively and retransmits data automatically by outdated feedback information.

推导了系统在时延反馈条件下的频谱效率和中断概率的闭合表达式，分析了时延反馈对于系统性能的影响。

In this paper, the finite-difference time-domain formation of Maxwell's equation is deduced and coded in perfectly matched layer in three-dimension cylindrical complex coordinates.

在三维柱坐系下推导了完全匹配层吸收边界条件的时域有限差分表达式，从而把 FDTD方法推广到完全三维柱坐标系中。

Themapping function sequences including circular cutouts and elliptical cutouts aregiven in this chapter.

然后为方便地满足圆柱壳大开孔的边界条件，通过复变函数方法中的用来求解多边形映射问题的Schwarz-Christoffel积分表达式，将圆柱壳展开面上的非圆非椭的开孔边界曲线保角映射成为单位圆，给出了在不同开孔率情况下的关于圆孔和椭圆孔的保角映射函数的具体形式。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。