数值算法

Considering the numerically more stable properties of Normal Equation with Constraints and Hachtel's augmented matrix method for SE, all telemetered and virtual measurements are classified reasonably. Using blocked and sparse matrices technology, a new SE algorithm with computing speediness and numerical stability is proposed.

借鉴WLS估计中带等式约束的正规方程法和Hachtel法数值稳定性更强的优点，将遥测量和虚拟量测合理分类，并采用分块和稀疏矩阵技术形成了一种计算速度快、数值稳定性好的状态估计改进算法。

The control volume integration was applied to deduce the discrete expressions of the convection-diffusion equations. The staggered grid and SIMPLE algorithm were introduced to deal with coupling between pressure and velocity, and then the numerical computation expressions of such variables as fluid flow velocity and pressure were deduced. Using the backward difference method and incremental theory to discretize the governing equations for fields of chemical reaction, material structure and chemorheology, the numerical computation expressions of variables such as the monomer conversion, average molecular weight and fluid viscosity were constructed.

应用控制容积积分法导出了对流—扩散方程的离散表达式，引入交错网格技术与SIMPLE算法，实现了耦合的压力场与速度场的分离式求解，推导得到了流体的流动速度、压力等物理量的数值计算式；采用向后差分方法和增量方法，实现了化学反应场、材料结构场、化学流变场控制方程的离散，获得了反应转化率、聚合物平均相对分子质量、流体黏度等物理量的数值计算式。

Because the derivation of the extended system has a block lower triangular form, the method of splitting iteration is applied to compute simple bifurcation point, not only computational work is reduced, but also local quadratic convergence is achieved.

由于所构造的扩充系统的导数具有分块下三角形式，采用分块迭代的方法进行数值求解，不仅减少了计算量，而且是二次收敛的，从而为Navier-Stokes方程非退化简单分歧点的数值逼近提供了有效的算法。

To obtain efficient survivability, this paper presents a novel restorable lightpath selection algorithm based on the automatically switched optical network frame. A numerical simulation is made in term of this routing selection algorithm. The result shows that the traffic has an obvious balancing trend; the block probability of connection requests has been reduced. At the same time, this algorithm has an excellent performance on bandwidth utility and sharing of the restoration resources.

摘要为了获得高效的网络生存性能，基于自动交换光网络的框架，该文提出了一种新型的可恢复路径选择算法-联合可变权重可恢复路径选择算法，并进行了数值仿真分析，仿真结果表明，此恢复路径选择算法具有明显的业务量均衡能力，并降低了动态连接请求的阻塞概率，同时具有良好的带宽利用率和恢复资源共享效率。

The above problems are studied in this thesis. First, the implicit NND scheme with mix flux splitting method proposed by Zhang Hanxin that is first order accurate in time and second order in space is modified. The modified scheme keeps the characteristics of fast convergence and is second order accurate both in time and space. It can be capable of simulating the unsteacly flow. Second, the topological method founded by Zhang Hanxin is improved to study the characteristics of vortex near the singular point on its axis and the cross streamlines on the longitudinal section passing the vortex axis. On the basis of topological results, a program which visualises numerical results is made out. It can help us analyse the characteristics of vortex motion.

本文对上述问题做了研究：第一，在数值模拟方面，借助于张涵信提出的NND算法和混合通量法，我们将他建立的时间为一阶、空间为二阶精度的快速隐式算法推广为时间和空间均为二阶精度的算法，这样做保留了原格式收敛快的特点，而且能适用于真实的非定常流态的计算；第二，将张涵信的拓扑分析方法加以推广，研究了涡轴附近及破裂点邻域内流场的空间特征，并以这些拓扑分析结果为指导，研制了一套显示计算结果的软件，这一软件能很好地帮助我们分析流场的计算结果和旋涡演变的特征。

To pre-estimate the formability of complex aircraft skin parts and simulate the whole deformation processes, a finite element simulation system-STRETCHFORM is developed to assist the manufacture according to the stretch-forming feature of skin parts.

针对飞机复杂蒙皮拉伸成形特点，基于静态隐式算法开发了复杂蒙皮拉形数值模拟系统STRETCH FORM。系统分为前置处理、核心求解和后置处理3个模块。介绍了系统各模块的主要功能以及机构运动、静态隐式有限元算法和接触搜索算法等关键技术理论。

Moreover, we discuss the relationship between the residual norm of the quasi-refined approximate eigenpair and that of the refined eigenpair, and the quasi-refined biorthogonalization Lanczos algorithm is given. Some numerical experiments are carried on, and the results illustrate that the newalgorithm is superior to the classic one. 2.We propose the semi-refined biorthogonalization Lanczos method which is based on the refined projection idea.

将精化投影方法的思想和拟精化思想相结合，提出了拟精化双正交Lanczos方法，建立了拟精化近似特征对和精化近似特征对对应的残量范数之间的关系，给出了拟精化双正交 Lanczos算法，并进行了数值实验，具体算例表明，该算法比双正交Lanczos算法优越； 2。

In this paper we propose a new image reconstruction algorithm for electrical impedance tomography-Quasi-Newton algorithm, based on modified Bk. Numerical tests were made to verify the effectiveness of this algorithm.

本文提出了一种新的电阻抗成像图像重建算法—基于修正Bk的拟Newton类算法，并通过数值试验验证了该算法的有效性。

In this paper we propose a new image reconstruction algorithm for electrical impedance tomography-Quasi-Newton algorithm, based on modified Bk. Numerical tests were made to verify the effectiveness of this algorithm.

摘 要 本文提出了一种新的电阻抗成像图像重建算法—基于修正Bk的拟Newton类算法，并通过数值试验验证了该算法的有效性。

In the numerical method has many extrapolation algorithms, the Romberg squaring algorithm is one kind of commonly used extrapolation algorithm, it is one kind of sector divides in half the accelerating convergence method gradually.

数值方法中有许多外推算法，龙贝格求积算法是一种常用的外推算法，它是一种区间逐次分半的加速收敛方法。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。