查询词典 sampling methods

This paper utilizes FFT after undersampling to analyze the relationship between the estimation of sinusoidal parameters and corresponding actual values on the basis of bandpass sampling theorem. In addition, the errors of parameter estimation using phase difference are deduced strictly.

摘要该文从带通采样定理出发，分析了欠采样后利用FFT估得的正弦信号参数与真实值之间的关系，并对欠采样下基于相位差分法的参数估计的误差进行了严格的推导。

The scattering coefficients of a single charged sphere are deduced. And with spherical vector wave functions and addition theorem, the scattering coefficients of multiple charged and uncharged spheres are derived. The sampling method of simulating a Gaussian beam in use of MC is provided.

详细推导了单个带电球粒子的散射系数；并采用矢量波函数展开方法结合矢量波函数的加法定理导出了高斯波束入射多个带电/不带电球粒子的散射系数；提出了用MC模拟高斯波束的抽样方法。

A phase advancer has a main AC-AC frequency conversion circuit consisting of thyristors.When sampling circuit detects the zero passage signal produced in rotor current of motor,main circuit controlled with advanced microcomputer controlling technique will change the AC voltage of 380V,50HZ into compensating voltage with the same frequency as that of rotor voltage and rotor current 90°in phase lay to achieve the goal to raise the power factor of the motor.

由可控硅构成的交变频主电路，在采样电路检测到电机转子电流产生的过零信号后，经过先进的微机控制技术控制主电路，将380V、50HZ交流电压转换成转子频率相同，相位滞后转子电流90°的补偿电压，达到提高电动机功率因数的目的。

This study pays emphases on Sampling and examination of aerosol.

本实验的重点也是气溶胶的采样与检测。

Sampling and examination of aerosol is an important mean to research of atmospheric pollution.

气溶胶的采样检测是国内外研究大气污染的重要手段。

A study cased in Zhejiang Province, China, showed the fact that the three-phase sampling could produce the highest AFI area estimation precision.

用浙江省实际数据计算的结果表明：三相抽样精度明显比其他估计方法高。

Air quality information-sampling is very important to manage and control air cleaner.

空气质量采集对空气清新器的管理和控制起着关键的作用。

Smoking ; air pollution ; sampling survey

吸烟；大气污染；抽样调查

Objective］ GC analytical method for butyl ether in the workplace air using sampling by charcoal tube was studied.

目的］ 研究炭管采集空气中丁醚的气相色谱分析方法。

I initially used the Airbrush tool with some fairly broad strokes, sampling the colors that were already in the area of her neck.

我最初用喷枪工具，一些相当广泛的中风，采样的颜色已经在该地区的脖子上。

Pachomius manual labour was organized as an essential part of the monastic life; and since it is a principle of the monks as distinguished from the mendicants, that the body shall be self-supporting, external work of one sort or another has been an inevitable part of the life ever since.

根据圣pachomius体力劳动组织作为一个重要组成部分寺院生活；以来，这是一个原则的和尚，作为有别于乞丐，该机构应自支撑，对外工作的这种或那种已一个必然的一部分，生活至今。

In order to study the effects of parametrical rolling on the ship movement and tilts, in allusion to ship's navigating in regular following waves, the equation of ship rolling motion is transformed into normal Mathieu equation by proper variable replacement when strong parametrical excitation in restoring moment varied according to sine or cosine wave.

为研究参数横摇对船舶运动和倾覆的影响，通过对船在规则波上随浪航行时，恢复力矩中出现的1个以正余弦规律变化的强参数激励项进行适当的变量置换，将船舶的横摇运动方程转换成标准形式的Mathieu方程。