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Convergence of semi-iterative method was discussed by Varga, Young and HU Jia-gan when iterative matrix is symmetric. In this paper, using Chebyshev polynomial and its properties, we obtain the convergence of semi-iterative method for a class of antisymmetric iterative matrix.

本文依据Varga， Young，胡家赣书中介绍的迭代矩阵为对称阵时，半迭代法的收敛性的理论，以Chebyshev多项式及其基本性质作为基本工具，对一类反对称迭代矩阵，研究其半迭代法的收敛情况。

In the case of the iterative learning control for linear continuous system with the initial error, a kind of ILC approach with compensation to the initial error is presented using the theory of the two dimensional (2 D) linear continuous discrete system.

针对线性连续系统迭代学习控制中含有固定初始误差的情形，利用二维系统理论给出了一种带有初始误差修正的迭代学习控制方案和这种迭代学习控制规律收敛的条件，并说明由此设计的迭代学习控制器简单有效，可实现在初始时间段以外部分对期望轨迹的完全跟踪。

By For the Jacobi iterative method of Gauss - Seidel iterative method and the comparison Initial research iterative equation and the nature of the coefficient matrix iteration convergence speed impact.

本文通过了举例对Jacobi迭代法和Gauss-Seidel迭代法进行了比较，研究迭代初值和方程组系数矩阵性质对迭代法收敛速度的影响。

Firstly, the principle of the iteration method is presented, the characteristic of the method is analyzed. The downward continuation computation for model and practical data with noise of different variance is performed by means of iteration method.

首先介绍了迭代法的基本原理，分析迭代法的特点；然后利用迭代法对不同噪声水平的模型数据和实测数据进行向下延拓计算，研究噪声对迭代法的计算误差影响。

In order to speed up the convergence speed, the each one step of the Landwber iteration is discomposed into the matrix computation and solution and a quick iteration scheme is given for the matrix computation. The relevant accelerated algorithm is given too. Numerical example proves that the accelerated algorithm can quicken convergence speed, reduce the calculation burden, and overcome the obstacle of application of Landweber method of iterated regularization.

为了加快Landweber迭代收敛速度，将每一步Landweber迭代分解为矩阵计算和求解，对矩阵计算部分设计了一种快速迭代格式，并给出了相应的加速算法，通过数值实验验证了这种算法能够大大加快收敛速度，有效的减少计算量，解决了Landweber迭代正则化方法在实际应用中的障碍。

The reconstruction problem is ill-posed, so two optimal criterions, the least module and the smoothness criterion base on Tikhonov regularization technique, are introduced into reconstruction algorithm. Many regularization parameters choice strategies are investigated, and the TPA(Two—Parameter Algorithm) strategy which is based on the Morozov discrepancy principles, is implemented in two regularization reconstruction algorithms.Numerical experiment results show that the nonnegative and smoothness constraint condition can overcome the difficulty of iteration semiconvergent, preconditioned technique can improve convergence rate and reconstruction accuracy, smoothness regularization criterion can meliorate ill-posed problem of reconstruction and enhance iteration stability, and the TPA is an effective strategy of regularization parameters choice.

数值试验表明：在共轭梯度法中引入非负约束和光滑约束改善了迭代的"半收敛"性，非负约束保证了解的非负性，光滑约束抑制了重建解的振荡现象，约束算法的重建精度与无约束算法相比大幅度提高；在约束共轭梯度重建算法中引入预优技术，可以加快算法的收敛速度，提高迭代的稳定性和重建精度；引入光滑准则的正则化技术可以有效改善图像重建问题的不适定性，加快迭代的收敛速度，提高迭代的稳定性和图像重建质量，计算正则参数的TPA算法在闪光照相图像重建中是有效的。

If the pattern has a low rate of convergence, the time of the human and machines will be wasted and the answer are not surely attainable.So,we must look for the patterns with the high rate of convergence or try to settle some parameters of the iteration patterns (for instance the overrelaxation parameter of SOR iterative method).

本文第二章针对AOR迭代法考察了当线性方程组的系数矩阵A为(1，1)相容次序矩阵且其Jacobi特征值为纯虚数或零时的迭代收敛范围，最优参数(即最优松弛因子和最优加速因子)及与之相应的谱半径，并将此最优谱半径与相应的SOR的进行比较，定量的给出在不同条件下，AOR和SOR迭代法各有其优越性，从而圆满的解决了在这两种迭代法之间如何适当的选择最佳迭代法的问题。

Two He-Ne lasers have been designed in experiment,one with simplest 2D axisymmetric folded-combined cavity that are composed of a concave-plano-concave folded cavity and a plano-concave cavity , and other with simplest 3D axisymmetric folded-combined cavity that are composed of two concave-plano-concave folded cavities and a plano-concave cavity.

本文实验设计了由一个凹-平-凹折迭腔与一个平凹腔组合的二维轴对称折迭-组合腔型He-Ne激光器及由两个凹-平-凹折迭腔与一个平凹腔组合的最简单立体轴对称折迭-组合腔型He-Ne激光器。

For the sake of the image reconstruction efficiency we shortened the reconstruction time almost 100 times by parameter table method. In algebra iterative algorithm we found the range of relaxation parameter is very different. The range of relaxation parameter of ART was narrower than that of SIRT. Different methods of data access will influence on the quality of reconstruction image.

在代数迭代算法中，通过模拟图像的重建发现，ART算法和SIRT算法松弛因子的选择有很大的不同，SIRT的松弛因子选择范围偏小，而ART的松弛因子选择范围要宽得多；数据访问方式的不同，对重建的图像有一定的影响；提出了最优迭代次数的判据，避免了在迭代时迭代次数选取的盲目性。

Http://www.hkshingtat.com/index/back_music.mp3莎拉布莱曼斯卡波罗集市歌词译文赏析 Are you going to Scarborough Fair parsley sage rosemary and thyme Remember me to one who lives there she once was a true love of mine …… Tell her to make me a cambric shirt (Oh the side of a hill in the deep forest green) Parsley sage rosemary and thyme (Tracing of sparrow on the snow crested brown) Without no seams nor needle work (Blandets and bedclothes the child of the mountain) Then she'll be a true love of mine ……(Sleeps unaware of the clarion call) Tell her to find me on acre of land (On the side of a hill a sprinking of leaves) Parsley sage rosemary and thyme (Washes the grave with silery tears) Between the salt water and the sea stand (A soldier cleans and polishes a gun) Then she'll be a true love of mine …… Tell her to reap it with a sickle of leather (War bellows blazing in scarlet battalion) Parsley sage rosemary and thyme (Generals order their soldiers to kill) And gather it all in a bonch of heather (And to fight for a cause they're long ago forgotten) Then she'll be a true love of mine

斯卡布罗集市您去过斯卡布罗集市吗？芜荽，鼠尾草，迷迭香和百里香代我向那儿的一位姑娘问好她曾经是我的爱人。叫她替我做件麻布衣衫芜荽，鼠尾草，迷迭香和百里香(在白雪封顶的褐色山上追逐雀儿)上面不用缝口，也不用针线(大山是山之子的地毯和床单)她就会是我真正的爱人。(熟睡中不觉号角声声呼唤)叫她替我找一块地芜荽，鼠尾草，迷迭香和百里香(滴下的银色泪珠冲刷着坟茔)就在咸水和大海之间她就会是我真正的爱人。叫她用一把皮镰收割(战火轰隆，猩红的枪弹在狂呼)芜荽，鼠尾草，迷迭香和百里香(将军们命令麾下的士兵杀戮)将收割的石楠扎成一束(为一个早已遗忘的理由而战)她就会是我真正的爱人。

And Pharaoh spoke to Joseph, saying, Your father and your brothers have come to you.

47：5 法老对约瑟说，你父亲和你弟兄们到你这里来了。

Additionally, the approximate flattening of surface strip using lines linking midpoints on perpendicular lines between geodesic curves and the unconditional extreme value method are discussed.

提出了用测地线方程、曲面上两点间短程线来计算膜结构曲面测地线的方法，同时，采用测地线间垂线的中点连线和用无约束极值法进行空间条状曲面近似展开的分析。