收敛性

to reduce the impact of carrier frequency offset in ofdm system,this thesis designs a new carrier frequency offset estimation scheme for ofdm system.the carrier frequency offset estimation includes acquisition and tracking.we adopt variable step size adaptive algorithm.the acquisition range of the proposed algorithm is as large as one half of the overall signal bandwidth.through this method we can not only avoid the feedback by using forward error correction,but also reduce the times of complex multiplication in order to reduce the power consumption of the system.this algorithm not only has low complexity and fast convergence nut also can improve the demodulation performance of ofdm system.computer simulation illustrates the superior performance of the proposed algorithm with regard to estimation accuracy in both awgn channel and multi—path channel.

摘 要：为了减小正交频分复用系统受频率偏差的影响，在ofdm系统中设计了一种新的载波频偏估计算法。频偏估计包括跟踪和捕获两个阶段，文中采用变步长自适应算法来进行跟踪，这个跟踪算法的捕捉范围是整个信号带宽的一半。通过此方法，不但可以利用前向纠错的方式来避免反馈，而且可以缩减复数乘法的次数以降低计算复杂度和系统功耗。该方法运算复杂度低，并具有较好的收敛性，能改善odfm的解调性能。从计算机的仿真效果可以看出无论是在awgn信道上还是在多径信道上都表现出了卓越的性能。

On the other hand, an iterative hard shrinkage algorithm is obtained by using the generalized conditional gradient method, as well as convergent theorems for Solutions and stopping criterion.

此外，利用广义条件梯度法得到了迭代硬阈值算法，并给出了解的收敛性定理和停止准则。

Finally, the numerical results show this class of conjugate gradient methods is very efficient.

然后证明三种新算法在强Wolfe线搜索下的全局收敛性，数值验证表明这类共轭梯度法是比较有效的。

In this paper a class of new conjugate gradient methods are presented, with which the global convergence with generalized Wolfe line search is proven.

本文提出一族新的共轭梯度法，证明了其在推广的Wolfe非精确线搜索条件下具有全局收敛性。

The two Armijo-type line searches proposed in Chapter 4 are shown to guarantee the global convergence of the class of conjugate gradient methods.

在第四章提出的两种Armijo型线搜索下，针对不同的线搜索参数分别讨论了共轭梯度法簇的全局收敛性。

In terms of the minimum question of a positive definite quadratic function,a set of Newton directions in minimum points derived with an accurate single dimensional search are used to produce a set of conjugate direction ,and a proof of convergence is presented.

对正定二次函数极小问题，利用精确一维搜索所得极小点处的牛顿方向来生成一组共轭方向，并给出收敛性证明

In this dissertation, we presented the global convergence properties of nonlinear conjugate gradient methods without line search and with strong Wolfe conditions, Goldstein inexact line search.

本文给出了无约束最优化算法—非线性共轭梯度法在不需线搜索和用强Wolfe条件下以及用Goldstein非精确线搜索产生搜索步长情况下的全局收敛性证明。

Nonlinear Conjugate Gradient Method; Line Search; Sufficient Descent Direction; Global Convergence

基础科学，数学，运筹学非线性共轭梯度法；线性搜索；充分下降方向；全局收敛性

We introduce the basic concepts needed to analyze the estimation error in VC theory by showing the connection between Empirical Risk Minimization consistency and uniform convergence and illustrate necessary and sufficient conditions for the consistency of the ERM principle, that is for the convergence of the minimum of the empirical risk to the minimum of the expected risk.

为了整合最小化经验风险和最小化期望风险理论，我们将藉由最小化经验风险(Empirical Risk Minimization， ERM)及统一收敛性举例说明原理的必要与充份条件，以分析VC计算理论的误差估算所需的基本概念。

The paper considers applying generalized pattern search methods to linear equality constrained minimization and analyzes the global convergence.

本文的主要内容是对广义模式搜索算法关于线性等式约束最优化问题的全局收敛性做了一些研究。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。