乘法

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。

Definition : plural addition, the plural subtraction, multiplication complex, realistic Ministry for the imaginary part of the plural output, the same judge two plural.

定义方法：复数加法、复数减法、复数乘法、求实部，求虚部，将复数输出，判断两个复数相等。

It is compact in structure, stable and efficient for practical uses with high package density. 7. Based on negative binary coding method, a modified two-dimensional crossed-ring interconnection network and four subarrays outproduct technique, an optoelectronic parallel martix-vector complex multiplication processor is presented.

借助负二进制数字表达、空间编码加权-移位四区域复数外积乘法技术和改进的矩阵-矢量啮合算法，研制了光电混合并行处理的矩阵-矢量乘法器。

The weighted least square iteration computational equations and error estimate equations are given.

给出了加权最小二乘法的迭代计算公式和误差估计公式。

The computational error of mathematics learningdisabled students is due to opposite computational error.

而数学学习障碍学生常犯的错误为：运算符号的替代、分数乘法的错误和计算顺序的错误。

With the corresponding flow parameters measured through the experiments and the criterion equation mentioned above,the correlation formula of degassing efficiency of flow of gas/liquid two-phase flow through corrugated multicup isoflux gas anchor is obtained through the regression analysis using the least square method and the Gaussian elimination.The influences of the number of arris and concave depth and angle on degassing efficiency are analyzed.

利用量纲分析方法建立了气液两相流体在瓦棱状多杯等流型气锚中流动的准则方程；根据室内实验测得相应参数和准则方程，利用最小二乘法及高斯消去法进行回归分析，得到气液两相流体在瓦棱状多杯等流型气锚中流动时脱气效率的关联公式，并分析了棱数、凹入深度、角度对脱气效率的影响。

Since the shape function of EFM is constructed by Moving Least Square Method, the continuity of field function is better than ever.

EFM方法采用移动最小二乘法（Moving Least Square method，简称：MLS）构造形状函数，所得到的场函数连续性好，可以更加真实的反映场的实际分布情况。

Making use of the continuity of the shape function of moving least squares methods, this scheme can obtain fine fitting results and achieve multi-level continuous range image surface fitting, which are convenient for calculating surface characteristics of range image.

该方法充分利用最小二乘法形函数多阶连续的特点，能够保持在较高拟合精度的前提下获得深度图像曲面多阶连续的拟合结果，这种拟合结果为计算深度图像的曲面特性提供了便利。

Based on the modal superposition method and the exact solution of beam nature vibration, the motion equations of the simply supported and continuo...

基于模态叠加法和梁固有振动的精确解，建立了移动荷载作用下简支梁和连续梁的运动方程；利用样条最小二乘法逼近桥梁应变响应，由样条数值微分求得响应导数；再通过Tikhonov正则化方法结合奇异值分解技术得到了荷载识别的正则解。

The dissertation expatiate on the distribute algorithm. The key operation in FIR digital filter is multiplication operation, and it can convert multiplication to look up table and addition by adopting the distribute algorithm. It is very suitable to adopt distribute algorithm in FPGA, because there are look-up tables in FPGA.

基于FPGA本身具有查找表的结构，非常适合使用分布式算法，在FIR滤波器的结构设计上，将FIR滤波器中关键的乘法运算转化为查找表的过程和加法运算的过程。

The concept of equivalent rotationally rigidity is offered and the formula of rotationally rigidity is obtained.

主要做了如下几个方面的工作：对伸臂位于顶部的单层框架—筒体模型进行分析，提出了等效转动约束的概念和转动约束刚度的表达式。

Male cats normally do not need aftercare with the exception of the night after the anesthetic.

男猫通常不需要善后除了晚上的麻醉。