直接数值法

It is a direct scheme and can avoid accumulated error resulted by iterative methods.Value results have illustrated that our algorithm has high precision.

该方法是一种直接解法，可以减少迭代法所产生的误差积累，数值实验验证了理论分析的正确性，表明该算法具有很高的精度。

A numerical simulation technique based on the stable alternating direction implicit method and the upper bound element technique is presented and applied to simulations of extrusion directly following liquid infiltration which involves infiltration,solidification, and large plastic deformation in one process.

采用稳定的交替方向隐式有限差分方法、上限元法等数值计算方法模拟了融浸渗、凝固和大塑性变形为一体的液态浸渗后直接挤压的工艺过程。

The inverse radius vector transform is applied in this paper to change the boundless space into a bounded domain,so that the finite element method can be used in computing electromagnetic fields with open boundaries.

目前，在电磁场数值分析中，有限元法得到了广泛的应用，但一般都认为有限元法适用于有界空间中的电磁场问题，这是因为对于无界空间中的电磁场问题，方法的直接应用存在着一定的困难。

RESULTS: The numeric type timing variance would be obtained in database with the way of variable chronometry. The timing would be kept as a document of textual form with the way of document chronometry. All the operations would be counted time with the above ways. CONCLUSION: EpiData has the function of counting time.

结果：变量计时法可以直接在原数据库中得到数值型计时变量，文件计时法则将计时结果另存为文本格式的文件。2种方法均能实现对每个变量、每条记录、每次操作数据库的数据录入过程进行计时。

Firstly, this paper investigated roundly the basic theory of the ambient vibration method, analyzed systematically the main methods of ambient vibration identification, and discussed their advantages and disadvantages. Then we established the finite element model of structural dynamics and test model and analyzed their mutual relation, improved MUSIC method and correlation function method in the harmonic identification, and gave the subspace method and correlation function method based on continuous model, which is multi-harmonic retrieve technique. And then, this paper also puts forward least-squares method to estimate directly structural physical and modal parameters; this approach replaced the derivative operator in the continuous time model with an equivalent approximation, and estimated the physical parameters of structures by the least-squares method. And then, we discussed the approximation methods of derivative and their convergence. Finally, this paper researched the modal parameters of a frame structure by the simulation and test. The results demonstrated that subspace method, correlation function method and the least-squares method are effective and stable respectively.

全面地研究环境振动识别方法的基本理论，系统地分析环境振动识别方法的主要方法，讨论它们的优点和不足；建立结(来源：6666AB44C论文网www.abclunwen.com)构动力学的有限元模型和试验模型，分析有限元模型与试验模型之间的相互关系；改进谐波识别中的MUSIC识别方法和相关函数识别方法，给出大型结构模态识别的连续型的子空间分解识别方法和相关函数识别方法，这个方法是多元谐波识别方法；提出直接识别结构的物理参数和模态参数的最小二乘方法，这个方法利用导数的近似值代替导数值，并运用最小二乘方法识别结构的物理参数，讨论导数近似值的选择方法，分析算法的收敛性；通过仿真计算和模型实验，研究高层框架结构的模态参数识别，验证子空间分解识别方法、相关函数识别方法和最小二乘识别方法的有效性，算法的稳定性；从理论和试验两个方面分析和研究噪声对识别精度的影响，影响识别精度的因素，以及部分模态成分的模态参数不能够被识别的原因。

The values of Joule-Thomson coefficient derived from VDW and RK equations and the correction formula of state equation of ideal gas are compared with he measured values and the values obtained by conventional methods.

对采用VDW、RK方程直接求导法和理想气体状态方程的修正式求导法求得的焦耳－汤姆邀系数值与实测值、常规方法所得的值进行了对比。

To study numerical solution of the linear equations,the article presents direct method ,Jacobi iterate method and Gauss-seidel iterate method to approximately calculate,and has given its process in MATLAB.

为研究线性方程组的数值解，文章用直接解法、雅可比迭代法、高斯-赛德尔迭代法进行了近似计算，并给出在MATLAB中计算的程序。

In study on structure damage identification in time domain,error of numerical integral will affect directly accuracy of parameters resulted from reversion.

在结构损伤识别的时域法研究中，数值积分的误差将直接影响反演参数结果的精度。积分初值的未知、消除数值积分引入的误差是结构损伤反演计算中信号处理的难题。

By combination of the finite differential technique with the upper bound elemental technique, simulation for the technology of extrusion directly following liquid infiltration which involves infiltration, solidification, and large plastic deformation in one process has been realized and the essences of various technical processes have been revealed by their corresponding simulation results showing the variation of the infiltrated depth and the temperature field with time during infiltration, the punch position, the solidification development of the matrix alloy, the state of the composite within the deforming zone, and the forming load required at different times during extrusion.

采用有限差分法和上限元法相结合，对融浸渗、凝固和大塑性变形为一体的液态浸渗后直接挤压工艺过程进行了数值模拟，从浸渗时浸渗深度与坯料温度场随时间的变化以及挤压过程不同时刻的冲头压下位置、坯料凝固情况、变形区坯料状态、成形载荷大小等方面揭示了不同工艺条件下的各种挤压过程的实质。

Fluxgate sensor inducts the environment magnetic field, outputs the compass course signal to the CPU system. This signal then is transformed into digital signal. CPU processes it and then gains compass course. When use rotary mathod to measure the deviations, CPU first collects timed the compass course come from the Fluxgate sensor, then calculates automatically their deviations and the correspondent coefficients. Based on all this, CPU can calculates out the real-time magnetic course or the real-time ture course, then sents them to display on the digital displayer.

本系统采用磁通门传感器来直接敏感合成磁场，输出罗航向直流感应电压信号送A/D转换器进行转换，并经CPU计算处理得到罗航向度数值，以及利用&旋回法&测定自差时，CPU按照船舶旋回的角速度定时地采集罗航向度数值，在此基础上CPU自动地计算出各采集罗航向上的白差，再由此计算出自差系数，并实时地解算出磁航向值或真航向值，送数码显示器显示。

But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊！不用提了。提到肉，真是糟透了。