查询词典 centroid

In order to improve the measuring accuracy and efficiency, a high accuracy inspecting system for measuring the centroid and centroidal deviation of bullets based on three point method is designed. The working principle, relevant calculation formulae and the measuring equipment for measuring the centroid and centroidal deviation of bullets are presented, and the main factors affecting measuring precision are discussed. Then, a multiple measuring platform with automatic leveling and column structure autorotation of 90° is put forward.

为了提高其测量精度和效率，设计了基于三点法的高精度弹丸质偏心测量系统，介绍了测量原理、计算公式和测量设备，分析了测量误差产生的因素，提出了一种多测试平台和自动调平以及弹体自动旋转90°的设计思想。

For this purposewe need to develop some new methods and new techniques.For example we studythe properties of the"centroid curve"and the"auxiliary curve",and identify twoplanes in which these two curves are defined respectively;we also use the relationshipbetween the"centroid curve"and its"dual curve".

为此需要发展一些新技巧和新方法，例如研究由Abel积分之比定义的"质心曲线"和"辅助曲线"的几何性质，并把这两条在不同平面上定义的曲线放在同一个坐标系中考虑，或把"质心曲线"与其"对偶曲线"联系起来考虑。

A centroid adjustment method is presented which can maintain the horizontal pose robot body when one arm is hung on the overhead ground lines. The balance weight is moved by the servo motor according to the angle of inclination between the inspection robot body and the horizontal plane, which can be checked by the obliquitous sensor, so that the centroid position of inspection robot is concentrated on the arm that is hung on the overhead ground lines. Because the body of inspection robot is kept in horizontal pose, the other arm can accomplish corresponding task for attaching to or detaching from the overhead ground lines.

本文提出了一种质心调节方法，利用倾角传感器测量机器人车体与水平面之间的倾角，从而控制配重块移动电机的运动，将机器人的质心调节到悬挂于架空地线上的那只手臂上，因此能保证机器人车体保持水平姿态，确保需要脱线或上线的手臂完成相应的动作。

A measuring system which mainly consists of a high precision motorized translation stage of one dimension, POINT GREY Flea2-14S3 CCD camera and LED light source was designed and constructed. Based on a detailed analysis for experiment results, the periodic changing law of system error of LED facula centroid location in this measuring system was found. The results indicate that based on Flea2-14S3 CCD camera, the random error of facula centroid location is about 0.018 pixels, the system error is about 0.06 pixels, and the total error is about 0.063 pixels (1/15 pixels).

利用高精度一维电动平移台、POINT GREY Flea2-14S3 CCD 相机和LED 光源构建了测试系统，对测试结果进行研究和讨论，发现了测试系统LED 光斑质心定位系统误差的周期性变化规律，计算得到了基于Flea2-14S3 CCD 相机的光斑质心定位随机误差为0.018 pixels，系统误差为0.06 pixels，总体误差为0.063 pixels(约1/15 pixels)，能够应用于以光斑质心检测为手段的测量系统中。

A measuring system which mainly consists of a high precision motorized translation stage of one dimension, POINT GREY Flea2-14S3 CCD camera and LED light source was designed and constructed. Based on a detailed analysis for experiment results, the periodic changing law of system error of LED facula centroid location in this measuring system was found. The results indicate that based on Flea2-l4S3 CCD camera, the random error of facula centroid location is about 0.018 pixels, the system error is about 0.06 pixels, and the total error is about 0.063 pixels (1/15 pixels). According to the total error above, this CCD imager can be widely used in many measuring systems which count on facula centroid subpixel detection.

利用高精度一维电动平移台、POINT GREY Flea2-14S3 CCD相机和LED光源构建了测试系统，对测试结果进行研究和讨论，发现了测试系统LED光斑质心定位系统误差的周期性变化规律，计算得到了基于Flea2-14S3 CCD相机的光斑质心定位随机误差为0.018pixels，系统误差为0.06pixels，总体误差为0.063pixels（约1/15pixels），能够应用于以光斑质心检测为手段的测量系统中。

If the impulse force does not work on the centroid of projectile, the correction effect under OIT can achieve that when force work on the centroid, the machining and assemble tolerances can be lower, and a better correction can be achieved.

如果脉冲推力冲量没有作用于弹丸质心，有利触发时机的修正效果可以达到脉冲推力冲量作用于质心时的结果，降低修正弹药的加工装配精度要求，获得较理想的修正预期。

The given experimental results indicate that the measuring precision of the centroid and the centroidal deviation is no more than 0.1 mm and 0.01 mm respectively, which satisfies the qualification needs for high accuracy measuring the centroid and centroidal deviation of bullets.

给出的试验结果表明，质心测量精度≤0.1 mm，偏心测量精度≤0.01 mm，同时满足弹丸高精度质偏心的测量需求。

The issues of present seismic wavelet frequency caused by different concepts, such as apparent frequency, dominant frequency, peak frequency and centroid frequency, etc., which are defined by different methods, and understanding deviation, definition of seismic wavelet frequency for time and frequency domain are concluded and summarized. On this basis, three kinds of seismic wavelets in common use such as Ricker and Zinc wavelets as well as sine wavelet with exponential attenuation characteristics are analyzed and a conclude is achieved that apparent frequency and dominant frequency are consistent in essence, but peak frequency and centroid frequency as well as apparent frequency or dominant frequency are not completely consistent with different seismic wavelets. For actual seismic data, peak frequency can approximately be used as dominant frequency, but it is not suitable when seismic wavelet is known for it can give out any wrong knowledge and results.

针对目前地震子波频率由于定义方式出现的各种概念（视频率、主频、峰值频率、中心频率等）以及理解上出现的偏差等问题，首先从时间域定义和频率域定义2个方面进行了归纳和总结，并在此基础上对3种常用地震子波（Ricker子波，Zinc子波，正弦指数衰减子波）进行了分析和研究，得出视频率与主频概念一致，但不同地震子波的峰值频率、中心频率和视频率之间并不完全一致的结论；而对于实际地震资料，将峰值频率近似看作地震子波的主频是可以的，但在地震子波已知的情形下这样做是不恰当的，甚至可能会得出错误的结论和认识。

The simulation shows that the Corkscrew of beam centroid is a low frequency motion which overleaps the average eccentricity between centroid of beam and axis of accelerator and a dispersive effect.

计算结果显示，束心Corkscrew运动是叠加在束心平均偏轴上的一种横向运动，同时也是一种色散效应。

RSSI-based location is a hotspot in nowadays. This paper presents RSSI-based triangle and centroid location algorithm and trilateration algorithm, and analyses the average positioning error produced by this two methods. Simulation experiments prove that triangle and centroid location algorithm can obviously improve the location accuracy compared to trilateration algorithm.

基于RSSI的定位技术是现阶段研究的热点，本文提出了基于RSSI的三角形质心定位算法和三边测量法，并对两种算法所产生的平均定位误差进行仿真分析，仿真结果表明基于RSSI的三角形质心定位算法比基于RSSI的三边测量定位算法的定位精度有较大提高。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。