查询词典 accuracy of measurement

The main research work of this paper are focused on following areas:(1) Based on review of the theory and methods on measurements of particle fields, a new idea for obtaining particle size and velocity distribution within a spray through imaging the particle field with a laser light sheet was put forward;(2) A DPIV (Digital Particle Image Velocimetry) system, is fit for velocity measurements of low speed flows, was developed and expended to particle size distribution measurement;(3) An arithmetic for particle velocity field reconstruction was developed, and the velocity distribution of water mist was also obtained;(4) A software system for particle analysis, which based on image geometry emend, de-noise and image partition was developed, the parameters such as particle size distribution, mean diameter, number of particles, minimum and maximum diameter can be got with this system;(5) A water mist system was developed and its characteristics, such as droplet velocity, size distribution, number of droplets and spray cone angle under different conditions were obtained from experiments with PIVS;(6) The measurement results of water mist characteristics with PIVS were compared and analyzed with the simply simulated results, and in addition, in order to verify the accuracy of PIVS, some experiments were conducted with the standard particles, such as glass-ball with known mean diameter of 50μm and 115μm, metallic coated tracing particle with mean diameter of 12μm;(7) Some experimental studies on interaction of water mist with liquid pool fires were conducted.

本论文的主要工作包括以下几个方面：（1）在对粒子场测量的相关理论和具体方法进行综述分析的基础上，提出了通过采用激光片光对粒子场进行成像以获取其粒径和速度等参数分布的新思路；（2）研制了适宜于低速流动速度场测量的DPIV(Digital Particle Image Velocimetry)系统，并使其实现了对粒子场粒径分布的测量功能；（3）研制了基于粒子运动轨迹的速度场重建算法，获取了细水雾雾场的速度分布；（4）研制了基于几何校正、去噪、图象分割等图象处理方法的"粒度分析软件系统"，该系统既可分析给出粒子场的粒径分布直方图和平均粒径，还可给出粒子的数目以及最大、最小粒径等信息；（5）建立了一细水雾发生系统，并应用上述方法对不同压力条件下细水雾系统的雾场特性（如速度分布、雾滴粒径分布、雾滴的数目、喷雾张角以及雾化长度等）进行了实验测量研究；（6）对细水雾特性参数的PIVS测量结果与计算机简单模拟计算结果进行了定性比较分析，并利用平均粒径为50μm和115μm的玻璃球以及12μm的标准示踪粒子对PIVS系统的粒径和速度测量结果进行了实验验证，同时对其局限性进行了分析讨论；（7）对不同工况条件下细水雾与油池火相互作用的过程进行了模拟实验研究。

Accuracy: It is one of the important performance indexes for the sensors, an important one in relation to the accuracy of the whole measurement system.

精度：精度是传感器的一个重要的性能指标，它是关系到整个测量系统测量精度的一个重要环节。

Aimed to the problems of difficult installation and low measurement accuracy in high moisture, the grain moisture sensor has improved from the traditional parallel polar plate probe to plane polar plate probe. The plane polar probe with protect pole was used to decrease the affect of the stray capacitance and interference, and some critical parameters of the plane polar probe that influenced sensitivity and accuracy of the sensor were proposed. The finite element method was used to analyze the electric field and capacitance of the plane polar probe.

针对谷物水分传感器平行极板探头安装难度大、高水分测量精度低等问题，将平行极板探头结构改进成为平面极板探头结构，并且通过增加保护极板减小干扰和杂散电容的影响，提出影响传感器敏感性、精度的平面极板探头的几个参数，采用有限元分析方法较精确分析了探头的电场分布和电容。

It has been a big challenge to improve the measurement accuracy and the positioning accuracy of positioner.

如何提高平台测量系统的精度，从而提高平台的定位精度是目前超精密工作平台所面临的一大难题。

The relationships between main specifications of the instrument, such as tempe rature measurement accuracy of the instrument, temperature measurement sensitivi ty and temperature measurement range, and technical parameters, such as working wavelength of the instrument, bandwidth of amplifier and relative aperture of op tical system were analyzed.

分析了该系统的测量精度、测温灵敏度及测温范围等主要技术指标与激光源的能量、仪器的工作波长、放大器带宽、光学系统的相对孔径等技术参数间的关系。

The measurement accuracy of the photoelectric theodolite is decided based on measurement requirement of the ballistic trajectory. Two simple equations were derived mathematically, one expression for positioning error of the ballistic trajectory, angle error of the photoelectric theodolite, ranging error, target slant range and height when one instrument is used, another expression for positioning error of the ballistic trajectory, angel error of the photoelectric theodolite, target slant range and intersection angle when two symmetrical intersection instruments are used.

通过数学解析的方法，推导建立了2个简洁的公式：1）单站定位体制下弹道点位精度和光电经纬仪测角、测距精度以及目标斜距、高角之间的数学表达式；2）对称交会测量体制下弹道点位精度和光电经纬仪测角精度以及目标斜距、交会角之间的数学表达式。

With regarding to those factors affecting the measurement accuracy of spectrophotometer, the accuracy of wavelength was the most important one.

摘 要：通过对影响分光光度计测量准确性的因素进行分析，认为波长准确度是其中的主要因素。

Equal-accuracy digital tachometer not only have the higher of measurement accuracy, but also can be keep equal accuracy is in the entire measuring range.

而等精度数字转速表不仅有较高的测量精度，而且能够在整个测量范围内保持相等的精度。

Because how to improve the measurement accuracy of CT parameters is the key of low voltage method, the paper in detail introduces the electronic parameters measurement circuit, furthermore,the needed digital sinal source ,CT ratio measurement circuit ,the way of digital sampling ang sinal processing are emphasized in the paper.

文中详细介绍了CT 内部参数的测量原理及实现方法。在其中着重讨论了校验仪中所需的高精度测试信号源及变比测量电路的原理和实现、数字采样技术及数据的分析处理方法。

The conditions to measure accurately and the principles to select parameters of the multi— probes EST method are proposed, and the theoretical research, computer imitation and the experiment on a machine tool prove that these principles and suggestion are necessary and effective. The influence of the initial value errors of the probes, the installation error of the probes system, and the remaining error caused by the radical error motion are analyzed quantitively on the measurement accuracy of the multi—probes EST method. The influence of the error caused by the probe's axes which is not in a plane and the perpendicularity error of the plane which the probe's axes is in to the stational axis are discussed on the measurement results.

结合理论分析，对这些EST方法进行了计算机仿真分析和研究，重点研究了这些方法的应用条件和误差分离精度，所得出的结论是：三测头法EST基本上能实现各项误差的完全分离，适于在位测量使用；二测头法在恰当地选择测头安装角的条件下，可以得到较高测量精度，适于大型零件圆度、圆柱度、径向圆跳动和全跳动的在位测量；对置两测头时域法可以在一定程度上改善单测头法测量精度，但对随机径向误差无能为力；对置两测头频域法存在严重的谐波损失。

They weren't aggressive, but I yelled and threw a rock in their direction to get them off the trail and away from me, just in case.

他们没有侵略性，但我大喊，并在他们的方向扔石头让他们过的线索，远离我，以防万一。

In slot 2 in your bag put wrapping paper, quantity does not matter in this case.

在你的书包里槽2把包装纸、数量无关紧要。