系统的

Firstly expound the structure of the OFDM system, then analysis the working principle of OFDM communication and research into the key technologies in OFDM system: string conversion, sub-carrier modulation and demodulation, inverse Discrete Fourier Transformation, Discrete Fourier Transformation, cyclic prefix Insert, etc.

该文首先阐述了OFDM系统的结构，分析了OFDM通信系统的工作原理，研究了OFDM系统实现过程中串并转换、子载波调制解调、离散逆傅里叶变换、离散傅里叶变换、循环前缀插入等关键技术。

This invention relates to one MIMO-OFDM system simultaneous method, which comprises the following steps: a, processing relative computation by received local sequence and local ones to get relative peak and its side; b, processing filter on peak value and sides through one degree impact without limit; c, in the non integral digital sampling, the said peak value and its side are ordered to keep their position as time lag information; d, in the integral code sampling, it orders the peak value and its side and removes the sides and keeps relative peak position as time lag position to realize the simultaneous process.

本发明公开了一种MIMO-OFDM系统的同步方法，所述方法包括步骤：(1)将本地序列与接收到的序列进行相关运算，得到相关峰值及其旁瓣；(2)将所述相关峰值及其旁瓣通过一阶无限冲击响应数字滤波器进行滤波；(3)当所述MIMO-OFDM系统处于非整数倍码片抽样时，对所述相关峰值及其旁瓣进行排序，保留相关峰值及其旁瓣相应位置作为时延位置信息；(4)当所述MIMO-OFDM系统处于整数倍码片抽样时，对所述相关峰值及其旁瓣进行排序，并去除相关峰值旁瓣，保留相关峰值位置作为时延位置信息，从而实现同步。

Characteristics of free vibration and forced vibration of a damped system with dry frictional damping,viscous damping and c x·2 damping are analyzed and calculated,acceleration response of free-vibration of the dry frictional damped system has a sudden change when x· is zero,the change value is constant and depends only on the natural frequency ωn and the displacement xk due to dry friction.

本文对存在干摩擦阻尼、粘性阻尼和c.x2阻尼系统的自由振动及受迫振动特性进行了解析及数值计算，得到干摩擦阻尼系统自由振动的加速度响应在速度零点有一突变，这一变化量为定值，且只与系统固有频率ωn及摩擦当量位移xk有关。

At the same time, the paper study network Knowledge Discover in Dat...

在此基础上，提出了基于互联网的顾客关系管理系统，给出了系统总体设计框架，针对金牌公司开展了以顾客信息管理为基础的顾客关系管理系统的应用研究，并提出了提高公司CRM系统应用水平的措施。

The development trend of aeroengine control system is distributed control system,and communication based on data bus is the key technology of DCS.

航空发动机控制系统发展趋势是分布式控制系统，基于数据总线的通信技术是分布式控制系统的关键。

The overall design,system structure and functions,database structrues and software design are introduced.

介绍了浙江电能质量管理系统的整体设计构想、系统结构、功能和数据库结构以及系统的软件设计。

The core question is how to produce the modules , how to combine the products and system effectively and how to use the techniques of decompound and combinition.

模块如何产生，能否有效地组合成产品或系统，产品或系统的分解和组合的技巧和运用水平，是模块化的核心问题。模块化的目标是建立模块系统和对象系统。

In this paper, the degradation of forest and wetland ecosystem were studied .

本文对黄河三角洲森林生态系统退化和湿地生态系统的退化问题进行了系统的研究。

Along with the fast development of the power system, DEH has become the essential control system for steam turbines , especially for large steam turbines .

随着电力系统的飞速发展，数字电液控制系统成为当今汽轮机特别是大型汽轮机必不可少的控制系统。

The synchronization requirement and the synchronization policy of TMR active replication fault-tolerance system are emphasized with the assumption that the delitescence of error of process\'s kernel data is ignored, so that non-deterministic troubles can be thoroughly eliminated.

其次，按同步定理要求，重点对TMR主动任务复制容错系统的同步必要条件进行研究，通过排除主动复制任务进程的局部非确定性操作对系统同步机制的影响，使系统同步必要条件得到满足，从而设计实现TMR主动任务复制容错系统的同步策略和同步算法。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失