查询词典 iterative method for eigenvalue problems

Through theoretical derivation, the author proved that the Landweber method is the transmogrification of the iteration solution of the generalized inverse, so the phenomenon that the reconstructed images of Landweber through many iterative processes is close to those reconstructed by generalized inverse method is explained, then a new reconstruction algorithm, namely pre-iteration method is presented, which divides the process of reconstruction into two steps, namely off-line pre-iteration and on-line one-step reconstruction.

通过理论推导，作者证明了Landweber法实际上可归于广义逆矩阵迭代求解的变形，从而解释了Landweber法多次迭代后，趋于广义逆解的现象。

Polygenetic relationship among different types and resources of Narcissus was studied by RAPD and ISSR. And special marker in French type of Narcissus by RAPD was transferred to SCAR, which is more iterative and stable to identify this type materials.1. DNA concentration extracted from Narcissus by 2% CTAB little method was higher than that from other plants by this method or mass method. This indicated that tender leaf tissue with little cellulose was the direct cause of high deriving of Narcissus DNA.

本实验运用RAPD、ISSR对58份不同类型、不同来源的水仙材料进行亲缘关系研究，并将RAPD标记中法国水仙型的特异标记转化为重复性和稳定性好的SCAR标记，用于该类型材料的鉴定等研究工作中。

A character-codes model based pattern recognition method by using amplitude data of targets frequency response is proposed after the establishment of high frequency response equation of radar targets. The method uses the same unvariant character-codes to express the same target of different angles and uses sequential separating of regions of target's reference variables to obtain multiple coding vectors of all regions for every target. The category and pose of target can be determined after a two-staged classification processing such as coding processing of target range profile data and errors correcting processing of coded data. The two-stage classification results are used to target identification as posterior hypothesis to be tested by sufficient convincing and necessary convincing. The character-codes model based pattern recognition method is also adaptive to variation of target angles and controllable in error probability. Time-consuming and complicated iterative computation is not necessary in the train process of pattern recognition.

首先建立了雷达目标的高频频率响应方程，这种方程将目标多散射中心理论与目标局部谐振理论有机地结合起来；进而提出了目标多频响应结构成像方法，这种方法将瑞利区频率响应或谐振区频率响应曲线的不同部位用各种不同的近似方法去逼近，通过特征谱估计方法将目标的局部频响特征与宽带距离响应特征结合起来；然后提出了一种基于姿态角变化区域的序贯划分与多模匹配的特征编码识别方法，这种方法具有能适应目标姿态角的变化以及能控制识别的差错概率α等优点，在目标识别时只需要目标在少数有限个频率激励下的幅频响应数据。

To investigate the detecting capability of GPR in the dispersive medium, we propose a Finite Difference Time Domain method to solve Maxwells equations. We give an iterative method for calculation of the electrical displacement and magnetic fields in the Debye medium, and a method to compute the electric field from electrical displacement.

为了研究地质雷达在频散介质中的探测能力，提出了频散介质中时间域有限差分法计算麦克斯韦方程的方法，给出了满足Debye关系的频散介质中的电位移和磁场的迭代算法，以及由电位移计算电场的算法。

Coordinate sequence method is made up of the instruct information of polygon boundary x, y coordinate. It is the easiest polygon vector encoding method. The file structure of this method is easy, but because of the polygon boundary has stored two times, it will produce data redundancy, moreover, short of neighbor threshold information; Tree index encoding method make all the boundary points digitizing, store the coordinate sequence, connect the point index to boundary line, and then connect the line index to other polygons, so as to the tree index structure has came into being. It eliminates neighbor polygons boundary data redundancy problems; Topology structure encoding method is a method which by setting up a complete topology relationship structure, resolve the neighbor threshold and island information process problem. However, it makes arithmetic more complicated and makes database bigger.

坐标序列法是由多边形边界的x，y坐标对集合及说明信息组成，是最简单的一种多边形矢量编码法，文件结构简单，但多边形边界被存储两次产生数据冗余，而且缺少邻域信息；树状索引编码法是将所有边界点进行数字化，顺序存储坐标对，由点索引与边界线号相联系，以线索引与各多边形相联系，形成树状索引结构，消除了相邻多边形边界数据冗余问题；拓扑结构编码法是通过建立一个完整的拓扑关系结构，彻底解决邻域和岛状信息处理问题的方法，但增加了算法的复杂性和数据库的大小。

This thesis investigates the profile extraction and shape optimization on the result of topology optimization of planar compliant mechanisms. The main context includes the following work:(1) summarizing and analyzing the recent research status, some harvest and unsolved problems;(2) analyzing the conceptual design of planar path-generating compliant mechanisms and its mathematical model and tools;(3) Modifying the method of density contour as the method of profile extraction, and developing a method to optimize the density function in the profile extraction according to the requirement of the design of compliant mechanism;(4) developing a method to abstract the compliant mechanism into a form of links and joints by using the principle of connectivity on topology;(5) developing a method of shape optimization of planar path-generating compliant mechanisms, by representing the profile of the abstracted compliant mechanism as simple curves such as straight lines and arcs, establishing the models of the size optimization of the parameters of these curves, so that the compliant mechanism has a machinable shape;(6) At last, proving the feasibleness and effectiveness of the design method by making simulation design and validating it in FEA software.

主要工作包括：(1)分析了柔顺机构拓扑优化和形状优化的研究现状，分析了目前柔顺机构的研究重点、主要成果和尚未解决的问题；(2)分析了基于SIMP的柔顺机构概念设计方法及其相关工具和模型；(3)针对柔顺机构轮廓提取的特殊要求，提出了密度等值线法的改进方案，对密度函数插值点密度值进行优化，提出优化模型和选择优化算法；(4)根据轨迹输出平面全柔顺机构自身的形状特点，提出了轨迹输出平面全柔顺机构的抽象方法，即应用拓扑学上的连通性原理将柔顺机构抽象成杆件和结点形式，并对相应的数学原理进行了证明；(5)提出了平面全柔顺机构的形状还原和尺寸优化方法，对抽象的柔顺机构进行还原，将其轮廓还原成简单曲线的连接，从而建立尺寸优化模型，对机构进行尺寸优化设计，在得到可加工的机构轮廓的同时又能对关键部位进行特别处理；(6)进行了柔顺机构的数值仿真设计，并将所得设计结果导入商用有限元软件中进行仿真实验，证明了设计方法的可行性和有效性。

Z2Bn z$e0A0 Meshless method is a new numerical computation method that is developed rapidly in recent years. Without element mesh and based on the dispersed nodes to form approximate interpolative function dynamically, meshless method has distinct difference with traditional finite element method. Meshless method conquers the problems caused by mesh generation, mesh aberration and mesh move. With provides a new effective means to engineering problem, meshless method obtain highly recognition in international compute mechanics domain and engineering field.

6L！y6K1Q6h0k0 无网格方法是近年来迅速发展起来的一类新型数值计算方法，它们不借助单元网格而是基于离散结点动态构造近似插值函数，与传统的有限元方法有着显著的区别，克服了网格生成、网格畸变和网格移动引起的问题并为工程问题提供了一种新的有效分析方法，受到了国际计算力学界和工程界的高度重视。

In this paper, we used the regularization method and the best disturbed iteration to solve such more extensive equations: every kind of positive problems and inverse problems of the hyperbolic partial differential equation and parabolic equation. We give homologous methods to solve the positive problems and inverse problems of nonlinear Burgers equation and Boussinesq equation.

本文应用正则化方法和最佳摄动量法，解决了一类更广泛的双曲型和抛物型偏微分方程的各类正问题及反问题，对非线性的Burgers方程及Boussinesq方程的正问题及反问题，也给出了相应的求解方法。

Here I will mainly discuss the apply of matrix's eigenvalue and characteristic vector in some problems. Its apply is not only in the mathematics but also in other subjects include physics, chemistry, economy, management etc.

这里我们主要讨论矩阵的特征值、特征向量在某些问题中的应用，这些应用不止是体现在数学方面，同时在其他学科（包括物理、化学、经济、管理等等）中也有广泛地应用。

In this paper, the elemntary knowledge of oblique circulant matrix is described briefly and three inverse eigenvalue problems which a-re denoted by Ⅰ,Ⅱ,Ⅲ and best approximation problem which is denoted byⅣ on oblique circulant matrix are presented.

本文介绍了斜循回方阵的基本内容，提出了斜循回方阵的特征值反问题Ⅰ，Ⅱ，Ⅲ及其最佳逼近问题Ⅳ，给出了它们有解的充分必要条件及求解算法，并举出了相应的数值例子。

Nowadays, most of research are to build a transmutative Petri Nets through adding controlling place sets, controlling arc sets and controlling policy to the basic Petri Nets, while the Controlled Petri Nets could be used to argue many controlling theory problems conveniently and to induce many logically and physically supervisory and solve the Event Feedback Controlling Problems and State Feedback Controlling Problem in DEDS supervisory theory.

目前大多数的研究表现为在变形后的受控Petri网基础上，利用各种方法求得各种逻辑型、结构型控制器，解决DEDS监控理论中的事件反馈控制问题与状态反馈控制问题。

On one hand, there are discussions with the works council and union about extension of short time working up to the end of September.

一方面，有讨论，工程理事会和联盟关于延长工作时间短至9月底。