查询词典 spectrum

Objective To study the change tendency of air pollutants in Shenzhen, China in 2002-2005, further, to explore the relationship between disease spectrum and air pollution.

目的 分析深圳市2002-2005年空气污染物浓度的动态变化，为进一步研究疾病谱的改变与环境因素变化的相关关系打下基础。

This is based on the feature of changelessness of the intensity contour in the Fourier spectrum plane while object plane is moved in Fourier transform system.

根据傅里叶变换系统中物面平移其频谱面上光强分布不变的特点，提出一种利用二次傅里叶变换实现CCD精密定焦的方法。

A method of decoding encoded channelization code set information to determine the number of multicodes and the code offset in spread spectrum data transmission.

一种对信道化代码集信息解码以确定扩频数据传输中的多代码数目和代码偏移的方法。

Aiming at the project request, the paper firstly introduces the theory of Frequency Hopping Communication, the theory of sampling and the principle of spectrum analysis using discrete Fourier transform, then combined with the characteristic and superiority of FPGA designs a channelizing detection method for the carrier frequency in Ultrashort Frequency Hopping signal based on FPGA.

然后结合现代可编程器件FPGA的特点与优势，设计了一种基于FPGA技术的信道化电子侦察方案。

With the multiple spectrum character of the ultrasonic generator, an impedance model of ultrasonic transducer under the triple frequency harmonic is built.

本文利用超声电源的多频谱特性，推导出超声换能器在谐振频率三次谐波下的阻抗模型。

By analyzing the changes of spectrum of the characteristic functional groups, the mechanism and process of synthesis reaction were discussed.

研究结果表明合成反应初期是一个物理化学反应过程；在反应过程中目标产物存在一个最低点区域，在特征官能团上"枝接"其他官能团时，应有效地避免该反应时间区域。

Machine tool ; Cutting chatter ; Time-varying system ; AR model spectrum ; Modal damping ratio ; Characteristic root

机床；切削颤振；时变系统； AR模型谱；模态阻尼率；特征根

The models have been applied to an investigation on the chatter in a type Mx-4 lathe. An in-depth study has been made on the AR spectrum, the chatter modal damping ratio and the characteristic root of a time-varying system.

文中对时变金属切削过程颤振的AR谱特性、颤振模态的阻尼率、时变系统的特征根这三个方面都进行了深入的研究，指出了时变金属切削过程颤振的特点，提出了颤振状态下的机床切削系统仍然是稳定系统的观点。

Some characteristic peaks in Raman spectrum have been pointed out.

简单指出了拉曼光谱中的几个特征峰。

The paper also introduce definition and characteristic of Power Spectrum.

文中介绍了功率谱的定义、功率谱分析方法的特点，并对其计算原理和在实现过程中使用的函数加以详细的叙述。

The work of this paper is as follows: 1. Looking back the progressing history of the linear motor, introducing the features of the elevator driven by linear induction motor, radicating the topic of this paper "the digital frequency variable control of the elevator bi-side direct driven by linear induction motor". The research of this paper covers the conventional VVVF control, space vector based VVVF control, vector control and DTC.

本文主要开展了以下几个方面的工作： 1 回顾了直线电机发展历史，电机的驱动技术演变，特别是针对直线电机的驱动，简要介绍了直线感应电机驱动电梯的优点和不同结构类型，对传统的v／f控制，基于空间矢量法的v／f控制，矢量控制，和基于电压空间矢量的直接转矩控制进行了比较，确立了本课题的研究主题：直线感应电机双边直推式驱动电梯的全数字变频控制。

The article combines with the treatment of a superficial civil air defense work to introduce how the grouting method to improve the performance of the backfill soil.

文章从治理漂浮人防工事的角度提出了注浆技术在改善回填土性质方面的应用，并详细阐述了注浆技术的施工流程。