数值分析

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。

With the use of analytical and numerical analysis to analyse the stability and attractability of the network using the two learning rules, the associative memory of the network using higher-order projection algorithm is better than that of using higher-order Hebbian algorithm.

通过在解析和数值两方面对这两种学习规则下网络的稳定性和吸引性的分析，可以看出高阶投影规则下网络的联想记忆性能比高阶Hebb规则下的要好。

The effect of obstacle with special size on audibility factor of DW-ILS is analyzed,and the numerical results are obtained.

采用电磁感应定理计算出了特定尺寸障碍物对分米波仪表着陆系统航向天线辐射场的散射，得到了该障碍物对跑道中心线上可听度系数影响的数值结果，并对此做出了分析。

Backset current area, the important factor of burner performance was discussed on the basis of carrying on numerical simulation to the cement kiln with three-channel burner by the model of. RNG k-ε. The model that backset current area was divided into center backset current area, interior backset current area, and other backset current area was compared in three-dimensional condition.

在采用重整化群κ-ε模型对水泥窑用多通道燃烧器进行数值模拟的基础上，针对影响燃烧器性能的重要指标－回流区进行讨论，将三维条件下燃烧器的流场分布与传统燃烧器流场进行劝比，提出了三维条件下燃烧器回流区分为中心回流区、内回流区、外回流区3个回流区的分布模型，并分析了影响回流区的直流风和旋流风2个重要因素。

The results of prediction agree well with the experimental ones. It proves that the thermo-mechanical analysis、the neural network models of flow stress and microstructure as well as the numerical simulation system developed combining coupled thermal-mechanical rigid-viscoplastic FEM with BP neural networks are reliable to describe the hot back extrusion process of Ti15-3 alloy truly. The simulation system has good prediction capacity for the microstructure evolution of Ti-15-3 alloy during hot backward extrusion and after solution treatment. It can be used to replace the experiments for predicting the flowing laws and the distribution of microstructure.

由此证明，本文的热力耦合理论分析、流变应力及显微组织的神经网络预测模型以及采用三维热力耦合刚粘塑性有限元与三层向后传播的人工神经网络相结合的方法开发的Ti-15-3合金筒形件热反挤成形的显微组织数值模拟系统是可靠的，能够真实地描述Ti-15-3合金热反挤工艺过程，并对其反挤成形及固溶处理后的显微组织具有很好的预测能力，可以被用来代替预测其反挤成形规律和组织分布情况的试验。

Methods According to Balthazar CT imaging manifestations, 110 cases with acute pancreatitis were chosen and classified into five grades, then compared with corresponding serum, urine amylase and C-reaction protein.

选取急性胰腺炎病例110例，将其CT表现分为5级，各级分别与其相应的生化指标数值进行比较与分析。

In this paper, an extended divide and conquer algorithm is intended proposed, which is for solving the real symmetric band generalized eigenvalue problem under distributing environment Eigenvalue partition theorem is presented and proved Based on divide and conquer by extension, this algorithm computes generalized eigenpaires of symmetric band matrix pencil by bisection and generalized Rayleigh quotient iteration Theoretic analysis and numerical results show that this algorithm is better than the classic software package LAPACK when bandwidth is small and the scale is large Combined with multisection, which has good parallelism, it got good effects under distributed environments

提出了分布式环境下计算对称带状广义特征值问题的一种扩展分治算法，给出了特征值分割定理及其证明算法在扩展分治的基础上，利用二分压缩结合广义Rayleigh商迭代计算广义特征对理论分析和数值实验表明，对于窄带宽大规模的广义特征值问题，该分治算法明显优于LAPACK软件包结合并行性好的多分法，在分布式环境下获得了很好的并行效果1 引言本文研究了对称带状广义特征值问题Ax =λBx ( 1)的并行计算，其中，A ，B均为半带宽为r的n阶实对称带状矩阵且其中之一是正定的本文总假设B是正定的求解此问题有两种传统方法，第1种方法是通过计算矩阵B的Cholesky分解，将问题( 1)转化为标准特征值问题[1～3] ，进一步

A theoretical model is built to investigate the simulation of the infrared characteristic of the metal structure with the PCM false target.Structure parameters of the PCM false target that suit for the simulation are investigated numerically.According to the results,further request on the improvement of the thermal conductivity of PCM is presented.An experimental platform is built and the numerical model is validated experimentally.Three key thermal characteristic components of the false tank(barbette,wheel and front armor plate) are manufactured and tested,and good results are obtained.A method for the thermal conductivity enhancing of PCM by using aluminum fins is studied,the influence of the structure parameters of PCM plates to the simulation effects are investigated numerically,and the reasonable configuration parameters of the PCM plates used to simulate the steel plates of different thickness are obtained.In the study of the application of heat convection method in IR false target,a passive infrared simulation system is designed to simulate the infrared characteristic of metal constructions.The system is made up of pipe-plate,pump,receiver,and working fluid.

在相变材料应用于红外示假的研究中，通过数值模拟，研究确定了适用于制作假目标的相变材料各物性参数的范围，分析了相变材料制作假目标的可行性，并根据所得结果，选取石蜡为研究对象，建立了相变材料模拟金属构件红外特征的理论模型，研究了适用于模拟各金属构件红外特征的相变材料假目标的相关结构参数，得出了相变材料假目标模拟各金属构件红外特征的理论结果，并对相变材料的导热系数这一物性提出了进一步的改进要求；搭建了假目标实验平台，验证了所建理论模型的准确性；以坦克假目标为研究对象，制作了炮塔、负重轮和前上装甲板三个坦克假目标的关键红外热特征部件，并进行了野外实验，取得了较好的结果；以添加铝肋片作为改进相变材料导热能力的手段，理论研究了此类导热增强型相变材料的相关结构参数对模拟效果的影响，得出了模拟不同厚度钢板红外特征的导热增强型相变材料的结构参数及模拟效果。

The barycentric Lagrange interpolation collocation method for solving initial value problems of differential equation is introduced.

本文首先分析了重心Lagrange插值的基本性质，给出了采用重心Lagrange插值逼近任意连续函数的数值算法。

Then, the tests measuring results were compared with the numerical simulation results, which were found to be in good agreement.

同时将试验测试结果与数值模拟结果进行对比分析，取得了较好的一致性。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。