调制

To solve the coupled wave function of nonlinear recording hologram, the linearization method was advanced, and two modulating models of refractive index were adopted, the convex curve and the concave curve.

采用折射率调制特性为上凸型和下凹型的调制曲线，提出了线性化求解非线性记录全息图耦合波方程的方法。

Taking the reflective phase hologram grating as an example, the spectral properties of the gratings were analyzed, for recording material with refractivity modulated in the convex curve and concave curve, by the coupled-wave theory.

以反射相位型全息光栅为例，用耦合波理论分析计算了记录介质折射率调制为上凸型和下凹型调制曲线的体全息图的衍射光谱特性。

Firstly, we describe the fundamental theory and types of the electrooptical modulators in detail, and make an introduction to the means used to analyze the modulators, especially, to the Schwartz-Christoffel conformal mapping technique.

本文首先详细的阐述了电光调制器的基本原理和类型，就研究调制器的方法作了介绍，特别是对本文采用的研究方法―施瓦兹保角变换的基本原理作了具体的分析。

This paper describes various methods of analog modulation based on Convolution Theorem and Hilbert Transform unitedly to simplify the theoretical analysis in the" communication principle" course.

本文基于信号处理概念中的卷积定理和希尔伯特变换统一地描述各种模拟调制方式(括DSB，SSB，AM，FM)原理，旨在简化"通信基础"课程中关于模拟调制理论的分析。

For aeronautical static converter then three-phase unbalanced load, made use of four-leg three-phase main circuit topology solution based on abc coordinates of the three-dimensional vector control, so that the switch to select the vector and duty more than a simple calculation, a significant reduction in the modulation of the complexity of the algorithm.

为解决航空静止变流器在不平衡负载情况下不能正常工作的问题，提出了三相四桥臂主电路拓扑解决方案，并采用基于abc 坐标系下的三维空间矢量调制，使开关矢量的选取和占空比的计算简单化，显著降低了调制算法的复杂性。

The results show the temporal pulse shape modulation is affected by the broadening factor and the delay time, as spectrum modulation is only affected by the delay time, and the intensity factor changes similarly with the cosine function of the phase factor.

研究结果表明，时间调制与基元脉冲的展宽量及相邻脉冲之间的延迟时间有关，光谱调制只与相邻脉冲之间的延迟时间有关，而强度的演化则与相位因子的余弦函数演化具有一定的相似性。

In this paper,a design method of two dimensional Linear Phase Nearly Perfect Reconstruction filter banks based on a new class of cosine modulation systems is presented,which can be described as follow: firstly,the Parks-McClellan algorithm is adopted for designing the prototype filter,then by employing cosine modulation,a series of analysis and synthesis filters can be obtained,accordingly a one-dimensional LP-NPR filter banks can be constructed;Secondly,cascading two one-dimensional LP-NPR filter banks in the form of tree structure and using the unimodular transformation,a two dimensional nonseparable LP-NPR filter banks can be obtained.

提出了一种基于一类新余弦调制系统的二维线性相位-近似完全重构滤波器组的设计方法，设计过程分为两个步骤：首先采用Parks-McClellan算法来计原型滤波器，再经过余弦调制能到一系列的线性相位分析和综合滤波器，从而可以构造一维LP-NPR滤波器组；然后利用树状结构来结合两个一维LP-NPR滤波器组，并运用单位模变换，可以得到二维不可分离LP-NPR滤波器组。

Actually ,signals are processed from low frequency domain to high one by modulation firstly and alternating current amplification secondly.It can also improve anti-interference抗干扰 ability of circuit and signal to noise ratio of signals.

实际中往往采用更有效的先调制而后交流放大，将信号从低频区推移到高频区，也可以提高电路的抗干扰能力和信实际中往往采用更有效的先调制而后交流放大，将信号从低频区推移到高频区，号的信噪比。

A modem with a maximum data transfer rate of 9,600 bits per second.

9，600bps 调制解调器最大数据传输速率为 9，600bps 的调制解调器。

By means of a linear array CCD lightintensity distribution measuring system, via the variation of the frequency and the power of ultrasonic wave, the direction control and the intensity modulation for the laser beam can be carried out. The relation curve between acoustooptic deflexion and modulation measurement is given.

在实验中，应用线阵CCD光强分布测量仪等，通过改变超声波的频率和功率，分别实现了对激光束方向的控制和强度的调制；定量给出了声光偏转量的关系曲线和声光调制测量的关系曲线。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。