查询词典 algebraic geometry

In several recent years, the linear encoding algorithm of the LDPC codes has also met with success. But the algebraic structure and algebraically constructing method of LDPC codes have still many problems need to be researched.

近年来LDPC码的线性复杂度编码算法有所突破，但它的H矩阵的代数结构及其构造方法，还有许多问题尚待研究。

In this paper, first we define a kind of transformation on the sequences of Boolean functions, and then analyze the changes of nonlinearity, algebraic degree and balancedness of Boolean functions under the transformation.

本文首先定义了对布尔函数的序列的一种变换，并分析了进行此种变换后布尔函数的非线性度、代数次数与平衡性的变化情况，最终在此基础上提出一种新的递归构造方法，可以构造出非线性度很高的n元m阶n-m-1次弹性函数。

Some important characteristics of functions which have balancedness, correlation inimunityc propagation criterion or strict avalanche criterion are pointed out respectively; For example, presents the feature of the Walsh spectrum and the algebraic normal forms of functions with balanced correlation immunity.

分别指出了满足平衡性、相关免疫性、扩散性和严格雪崩特性等的布尔函数的一些重要特征，如关于平衡相关免疫函数的谱特征和其代数标准型的结构特征。

The alterative direct iterative, strong implicit procedure, preconditioning transpose-free variant of quasi-minimum residual method and biconjugate gradient stabilized method of the Krylov subspace methods were implemented in SIMPLER algorithm to solve the algebraic equations.

将交替方向隐式、强隐及Krylov子空间法中的TFQMR、Bi-CGSTAB方法实施于SIMPLER算法，作为其内迭代求解方法，比较了不同代数方程求解方法的收敛速度，并首次分析了它们对算法健壮性的影响。

Three century Diophantine one of the outstanding contribution that Greece algebra simplify, simplify algebraic created.

三世纪的丢番图的杰出贡献之一，就是把希腊代数学简化，开创了简化代数。

Chapter 1 is introduction.we introduce the importance of homological theory in Algebras, and the close relations with other algebraic branchs.

第一章为引言，主要介绍了同调理论在整个代数学中的重要位置以及与其它代数分支的密切联系。

Elastic and inelastic differential and integral cross sections for low-energy vibrational excitation of H2 by electron impact are studied with exact exchange. The resulting coupled integrodifferential equations are solved using a combination of linear-algebraic and R-matrix-propagator techniques.

严格交换势用于研究低能电子与H2分子的弹性和非弹性散射截面，线性代数方法和R-矩阵传播子相结合求解基于振动密耦合方法的积分-微分耦合方程组，由此得到收敛的散射微分截面和积分截面。

Both of the algorithms with two forms for the parallel data and fan beam data respectively are developed based on the interpolative algebraic reconstruction techniques.

这两个算法对于不同的相叠采样模式，具体表现为四个算法：平行束的虚拟探测器法、平行束的直接重建法、扇形束的虚拟探测器法和扇形束的直接重建法。

The numerical experiment results show that the imaging convergent speed of the direct demodulation imaging method is accelerated dramatically using the ways proposed in the present paper.Furthermore, the author proposes one way to improve timing performance of parallel interpolative algebraic reconstruction.

此外初步研究了平行束的插值代数重建算法，在求像素投影地址时利用像素与像素投影之间的相关性和图像区域的对称性来提高插值代数重建算法重建图像的速度。

The main findings in this thesis are as follows:(1) Through the algebraic analyzing of the hydrologic map and the analysis and processing of the digital image, one could learn the knowledgement of the electronic map and digital image.

主要成果如下：(1)通过水文等值线图的代数分析、数字图像本质分析，加深了对电子地图和数字图像的认识。

You can snipe the second and third union leaders from this position.

您可以鹬第二和第三工会领袖从这一立场出发。

Aiming at the currently shortage of XML streams quality detecting, this paper proposes a new forecasting method of XML streams quality by least squares support vector machines, which is used the method of XML keys' vector matrix as windows, and vector product wavelet transform to multilevel decompose and refactor the XML streams series, that can fulfill real-time checking demand of XML quality, and ensure constraint, consist- ency and integrality. For even more adapting net load, it proposes a control strategy by weight and adaptive adjustment to ensure XML streams quality.

针对当前XML数据流质量检测存在的不足，提出构建XML键的矢量矩阵作为窗口，利用矢量积小波变换多级分解与重构XML数据流，再结合最小二乘支持向量机对XML数据流质量进行预测的一种方法，满足XML数据流质量重构时实时检测的要求，保证XML数据的约束性、一致性与完整性；为了更好的适应网络负载，采取加权与自适应窗口调整等调度策略充分保证XML数据流的质量检测。