数值计算

The wave number is expanded into asymptotic series in terms of a small parameter. This method is exact and can approach any accuracy desired.

这一方法本身是精确的，它能达到任意所需的精度，然而四层和五层波导结构的数值计算实例表明，仅二阶近似解就足够精确了。

The foundation of this system provides a good reference to promote the standardization and intelligence of the overhaul and maintenance of vacuum switches. This paper develops a special HF pulse power supply for internal pressure estimation, which achieves the output of HF-HV sinusoidal pulse wave whose frequency and amplitude can be modified respectively, and meets the design requirements according to the results of Simulink simulation and practical experiments. With the help of AT89S52, this paper designs an I~2C serial bus based signal detection system for peak value signal acquisition of HF pulse currents, which communicates with the upper computer by asynchronous serial communication for uploading the data. In the upper computer, a human computer interface is developed by Matlab software, whose functions are to do some computation and graphic display, such as calibrating the relation curve of vacuum degree and peak value of HF pulse currents, vacuum degree computation, and vacuum lifetime evaluation analysis basing on grey forecasting model as well as making relative suggestions.

本文研制了用于真空度检测的高频脉冲电源，通过Simulink仿真和试验检验其满足设计要求，实现了电压幅值和频率独立可调的正弦波高频高压脉冲输出；利用以AT89S52为核心基于I~2C串行总线的信号检测系统实现高频脉冲电流峰值信号的采集，通过异步串行通信实现单片机与计算机之间的数据通信，将检测数据传至上位机；在上位机利用Matlab开发人机交互界面，实现相关数据处理和图形显示，包括真空度——高频脉冲电流峰值关系曲线标定、真空度数值计算、基于灰色预测模型的真空寿命评估分析和提出相应决策建议。

In this paper, quantum theory, the use of time evolution operator obtained by the first method for the system density operator of any time, and atomic reduced density matrix, and the atomic dipole squeezing conditions, numerical study of the mixed state -type atom of the three-level with single-mode optical field coherent interaction of atomic dipole squeezing effect.

本文采用全量子理论，运用时间演化算符方法先求出所求系统任意时刻的密度算符，和原子的约化密度矩阵，以及原子偶极压缩的条件，数值计算地研究了混合态型3能级与单模相干光场相互作用时原子的偶极压缩效应。

A large uumber of numerical calculations using the analytic formula and the dispersion equation have been candied out on the relations of the attenuation and phase constant with wave frequency, thickness and conductivity of the lossy layer.

此式适用于截止频率附近，通过解析表达式和波导模式色散方程，对衰减常数和相位常数进行了大量数值计算，得到了它们随损耗层厚度、频率以及损耗层电导率的变化规律，两种方法所获得的结果有较好的一致性，研究表明，损耗强度和损耗层厚度的变化会改变波导中电磁模式的色散和简并特性，对于改善高功率回旋行波放大器中注波互作用带宽和模式竞争非常有益。

The effect of different discharge electrodes and settings on the experiment results is discussed in terms of average current density and relative deviation.

采用实验和数值计算相结合的方法，以极板表面平均电流密度、电流密度相对标准差为指标对电场性能进行了评价和预测，给出了几种电场性能较好的电极配置形式和几何参数调整范围。

Both the fuzziness and the randomness of the basic variable and the state variable are considered in the present method.

结合工程实际，提出了非闭合隶属函数的截断可能性分布模型，并对模糊强度和模糊应力进行截断处理，给出了结构模糊随机失效概率随截断参数的分布，并给出了结构模糊随机失效概率分布的数值计算方法。

The results of calculations are shown to be consistent with experimental results.

数值计算结果和试验结果一致。

Both the methods are totally different, and computation results are difficult to be linked up with each other.

上述两种方法是完全不同的，而且数值计算的结果彼此独立、难以光滑连接。

The characteristics of several types of air bearings are calculated with this method.

本文对气浮轴承的特性进行了分析并提出了基于有限元法的数值计算方法。

basic flow patterns in 3 types of suction boxes are studied respectively by both numerical calculation and model test, and the essential hydraulic indexes are listed. the boxes, including elbow inlet, bell-like inlet and dustpan-like inlet, are usually applied for vertical pump of low head.

采用数值计算和模型试验的方法分别研究了低扬程立式泵装置常用的肘形钟形和簸箕形等三种形式进水流道的基本流态，给出了表达这三种形式进水流道水力性能的主要指标。

For a big chunk of credit-card losses; the number of filings (and thus charge-off rates) would be rising again, whether

年美国个人破产法的一个改动使得破产登记急速下降，而后引起了信用卡大规模的亏损。

Eph. 4:23 And that you be renewed in the spirit of your mind

弗四23 而在你们心思的灵里得以更新