查询词典 algorithm theory

To solve this problem, an algorithm which can adaptively determine the double thresholds based on gradient histogram and minimum interclass variance and improve Canny operator was proposed. Theory and experiments show that the proposed algorithm is effective and correct.

为了对Canny算子的这一缺陷加以改进，提出了基于梯度幅度直方图和类内方差最小化原理自适应地求取双阈值的算法对大津法作出改进，理论推导和实验结果证明了该算法的正确性和有效性。

In order to overcome the handicap to extract line-segments from natural hand-printed Chinese characters, the extension is made to other structural features, and the generalized connected background region is defined, and its extraction and recognition algorithm are developed. This recognition algorithm is based on matrix singular decomposition and invariant transformation theory.

针对从自然手写体汉字中难以提取到笔段特征的难题，对汉字的其它结构类特征进行了扩充，提出了汉字的广义背景连通域的概念，并给出了提取广义背景连通域特征的算法以及基于矩阵奇异值分解与不变性变换的广义背景连通域特征的匹配算法。

Based on the summarizing of the exiting algorithms of the texture mapping and antialiasing, this paper goes deeply into the basic theory and processing of texture mapping. The texture compress algorithm which can satisfy the need of the memory and time is given for the stochastic sampling in the inverse texture mapping; the geometry transformation in the texture mapping are discussed and the concepts of the unitary parametrization and the patch parametrization is proposed, some kinds of the unitary parametrization methods of parametric surfaces and the geometry transformation in the patch parametrization are also presented; in order to solve the aliasing in the parametrization of intermediate surface-sphere in two-part texture mapping, an area-preserving transformation is presented also; to improve the quality of the graph the aliasing in the texture mapping is analyzed from the aspect of signal process, and the modified summed-area tables algorithms is proposed; the distortion of the scanline conversion algorithms under perspective transformation is analyzed and the proper interpolation algorithm is presented so the aliasing problem of the polyhedral object after the unitary parametrization is efficiently solved.

本文在总结现有的纹理映射和反走样算法的基础上，深入研究了纹理映射的基本原理与过程，根据反向纹理映射对纹理随机采样的特殊要求，提出了一种可满足存储空间和寻址时间的纹理压缩存储算法；通过对纹理映射中几何变换理论的进一步深入探讨，提出了整体参数化和面片参数化的概念，并给出了参数化曲面的各种整体参数化方法和面片参数化的几何变换形式；针对现有的两步映射算法所存在的中间曲面—球面的参数化问题，提出一种等积映射方法，较好地实现了由非参数化面片拼接而成的多面体表面的纹理映射；从信号采样的角度深入分析了纹理映射中走样产生的原因，提出了改进的区域求和表算法，使图形生成的效果有所提高；还分析了一般的扫描线算法在透视变换中所存在的问题，提出了一种正确的插值算法，从而解决了整体参数化后多面体表面纹理映射的几何变形问题。

A structure of space-time diversity virtual double-route weighting interference mitigating is proposed, and the corresponding practical algorithm is derived in detail using block matrix inversion formula and matrix inversion theory for mitigating interference signals from both other cells and other users of local cell in the DS-CDMA up-link communication case. Performances of such algorithm are thoroughly analyzed through simulation and analytical results. The up-link and down-link channel characters and their relationship of DS-CDMA communication system are thoroughly analyzed, and the relationship of space-time diversity weighting matrix between time division duplexing and frequency division duplexing these two different transmission ways is derived.

本论文深入地比较了DS-CDMA通信系统的上传情形与下传情形的信道特性及其它们相互之间的关系；深入地分析并得到了时分双工和频分双工两种不同的传输模式下的上传情形与下传情形的空时分集权系数矩阵之间的数量关系，从而使得能够利用在基站端所拥有的上传情形的空时分集接收权系数矩阵信息以及其他信息在基站端直接形成空时分集发射权系数矩阵；推导了下传情形移动用户接收机端的最优组合接收策略及其算法；进一步地，对时分双工传输模式下的下传情形的通信系统性能和频分双工传输模式下的下传情形的通信系统性能进行了深入的比较仿真研究。

The main results of this research are as follows:(1) A parallel algorithm for solving dense matrix linear equations on distributed-memory multi-computer is presented. Convergent velocity of this algorithm is better than parallel Jacobi method"s, and parallelism is better than Gauss-Seidel method"s. According to theoretical analysis, convergent conditions are given. Moreover numerical experiments indicate that results agree with theory.

主要完成了如下研究工作：(1)提出了一种求解系数矩阵为稠密矩阵的线性方程组的适合于MIMD分布式存储的并行迭代算法，该算法设计上兼取了Jacobi算法并行性好的优点和Gauss-Seidel算法收敛速度快的长处，并且在理论上给出了该算法成立的收敛性条件，并通过数值计算验证了此算法结果与理论相符合。

Based on Symplectic Algorithm, according to the theory of linear equation system and consistent conditions, a new algorithm is presented.

在辛算法的基础上，根据线性方程组理论和相容条件提出了一个求解约束的新算法。

According to the localization principle of the DV-Hop algorithm, this paper proposes three improvements including the estimation of average single hop distance, the calculation of distance between unknown nodes and reference nodes and the estimation of node positions. These improvements can be used independently or jointly to replace the corresponding steps in the DV-Hop algorithm. The localization performances are analyzed in theory and with simulations.

该文根据DV-Hop算法定位过程，在平均每跳距离估计、未知节点到各参考节点之间距离的计算和节点位置估计方法等3个方面进行了改进，分析和仿真了不同改进措施和综合改进的定位性能。

In the residual moveout, I firstly describe the Viterbi algorithm based on Markov process and compound decision theory and how to solve the shortest path problem using Viterbi algorithm.

在剩余时差校正中，首先阐述了基于Markov过程和复合判定理论的Viterbi算子；阐述了如何利用Viterbi算子来处理最短路经问题。

Mathieu function is the base of field theory analysis in elliptical cylinder coordinate system. So, firstly, detail investigation has been given about the problem of numerical analysis of Matheiu functions, based on the predecessor's contribution, an improved faster algorithm of numerical analysis and confirmation algorithm of Matheiu functions has been presented.

Mathieu函数是椭圆柱坐标系统下场论分析的基础，因此本文首先对Mathieu函数的数值计算问题进行了详细研究，并在前人基础上完善并进一步改进了目前被认为较为可行的数值算法，并提出了验证算法。

In order to solve the problem of chart projection transformation among all projections in shiphandling simulator,using the theory of power series spreading out and the method of trigonometric power series calculating back, a direct and reverse solving algorithm models of meridian arc length , and Gauss projection and Mercator projection transforming algorithm are introduced in this paper.

为了解决船舶操纵模拟器中不同投影方式海图的投影变换问题，应用幂级数展开理论和三角级数回求方法，给出了子午线弧长、等量纬度的直接正反解算法模型及高斯投影与墨卡托投影的相互转化算法。这些算法具有非常高的计算精度，避免了迭代运算，在船舶操纵模拟器中得到广泛应

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐