查询词典 fundamental algorithm

This paper first analyses and summarizes the ststus quo and evolution trend of encryption, some common used cryptograph are introduced, including the algorithms used in symmetric cryptosystem and asymmetirc cryptosystem. We describe the theory of each algorithms and compare the elliptic curve cryptosystem with the other two asymmetric cryptosystems to show the advantages of this algorithm. Second, the principle of ECC is discussed, including the math foundation of ECC, basic conception of elliptic curves, constructiong idea of ECC, operation on the elliptic curve and so on. Third, the current attacks of ECC were analyzed deeply, and an algorithm based on limited prime number field was constructed. We analyzed its realizability in theory, and implement it by using certain function of MIRACL software package. Latter half in this paper, the implementation model of a simple elliptic curve encryption system which based on GF has been introduced. The paper also put a deep analysis on the algorithm of point addition and point multiplication.

本文首先对密码技术的发展现状及其发展趋势进行了分析和综述，详细的介绍了私钥密码系统和公钥密码系统的发展，说明各种算法的原理和优缺点，并给出了一些典型的密码体制的简要分析，重点将椭圆曲线算法与其它几种公钥密码算法比较，说明椭圆曲线算法的优势；其次，探讨了椭圆曲线密码体制的原理，包括椭圆曲线密码的数学基础、基本概念、椭圆曲线密码体制的构造思想等问题；第三作者对椭圆曲线的攻击现状作了详细的分析，针对所使用的大素数域F_p，设计了素数域上安全椭圆曲线产生的算法，从理论上做了可实施性分析，从软件上做了具体实现；在本文的后半部分，提出了一个简单的基于有限素数域上的椭圆曲线加密方按算实现模型，并对SECES中设计的点加和点乘运算进行了深入分析。

Firstly, based on the method of pressure-velocity coupling introduced by SIMPLE algorithm and a revised method of solving the unsteady equation of stream function and vorticity on uniform grid, a special algorithm called primitive-variable-time-dependent approach is formed in the present study. In this algorithm the Navier-Stokes equation in primitive variable form is solved by using the time-dependent approach on non-uniform staggered grid system. The second-order accuracy finite difference is used for the first and second partial derivatives of all variables of the convective terms and diffusion terms.

首先，本文在SIMPLE算法系列处理速度与压力耦合问题的思路和均匀网格下改进的关于流函数涡量方程的数值求解方法的基础上，将非定常原始变量Navier-Stokes方程的求解推广至非等距交错网格剖分，形成了具有本文特色的原始变量时间推进方法，其中对流项和扩散项中各变量的各阶导数均采用二阶精度公式，包括温度在内的离散方程组采用ADI迭代方法求解。

This paper proposes an efficient clustering algorithm for Multivariate Time Series—PCA-CLUSTER.The algorithm applies principal component analysis to reduce the dimension of MTS,and subsequently chooses the principal component series of MTS to cluster by a K-nearest neighbor algorithm.

提出一种高效的多变量时间序列聚类算法PCA-CLUSTER，首先利用主成分分析对MTS数据降维；选取MTS数据的主成分序列进行K近邻聚类分析。

In this dissertation, incorporating the level set algorithm, the gradient projection method, the nonlinear mapping technique, the return mapping algorithm and the mean curvature flow technique into topological optimization theory, a level set algorithm for topology optimization with multi-material structures is put forward, which can optimize a problem with general objective functions, multi-constraints, multi-materials and multi-load cases.

同时，又将拓扑导数理论和水平集算法结合起来，提出了结构拓扑优化的拓扑导数与水平集算法，进一步提高了计算效率。

In decision tree algorithm,the famous one is ID3 algorithm,which was presented by Quinlan in 1986.It is not an algorithm increasing by degrees,and it uses information entropy as a standard to select attribute.

在决策树算法中属Quinlan于1986年提出的ID3算法最有名，它是非递增算法，并且采用信息熵作为属性选择的标准。

First, the paper introduces the sturcture of feedforward neural network and classical back-propagation learning algorithm, then systematic analysis and reserch are made to the various learning methods of RBFNN(Radical Basis Function Neural Network). The idea and algorithm frame of evolution strategy are presented and introduced to the learning algorithm of BP Neural network to improve the performance of it.

本文首先阐述了前向神经网络的结构以及经典的反向传播学习算法，尤其是对RBF网络的各种学习算法进行了比较系统的分析研究，然后又介绍了进化计算的思想和算法框架，并把这种算法思想引入到BP网络学习思想中去对BP算法进行了改进。

A modified differential evolution algorithm was presented. In the proposed algorithm, the difference vector, which is employed in mutating each individual by simple differential evolution algorithm, was recorded. Each mutated individual was taken as the center of a neighborhood, the corresponding difference vector as radius.

提出了一种改进的差分演化算法，该算法记录下了差分演化算法在对每个个体进行变异操作时的差向量，然后以被变异的个体作为邻域的中心，以所记录的差向量作为邻域的半径，再在这个邻域内进行一次挖掘式的搜索。

Genetic Algorithm is a random search algorithm imitating Biological genetics, and a kind of global optimization algorithm, one of the main approaches of evolutionary computation.

遗传算法是一种模仿生物遗传机制的随机搜索算法，它是一种全局优化算法，是进化计算的主要方法之一。

The simulation results show that the algorithm gets higher saved rebroadcast and reachability than the probabilistic algorithm and the counter-based algorithm.

模拟实验表明，本算法在节省转发率和可达率两个性能指标上均优于概率算法和计数器算法。

Based on the analysis and research of the domestic and overseas EIT algorithms, a practical and fast EIT algorithm with better resolution---Fast Newton's One-Step Error Reconstructor dynamic algorithm is studied and realized in this dissertation. Based on a great deal of experiment researches, the EIT algorithm and performance of hardware-measuring device needed by imaging system are analyzed.

本论文在分析、研究国内外有关电阻抗成像重建算法及其研究状况的基础上，研究实现了一种实用、快速、具有一定分辨率的电阻抗成像算法——快速牛顿一步误差重构动态算法，对成像算法进行了大量的实验研究和数据分析，对成像系统所采用的硬件测量装置的性能进行了研究。

I'm not an actor. I'm a professor of paleontology.

我不是演员，我是古生物学教授

Spider Network Web site that is a very image of the name.

网络蜘蛛即Web Spider，是一个非常形象的名字。