1) high-order approximation
高次近似
2) first-order approximation method
一次近似
1.
Based on the first-order approximation method(FAM),a non-Cartesian variables and a Cartesian variable s and a Cartesian u_2,which denote the arc-length stretch and the transverse displacement respectively,are employed to describe the deformation of the beam.
基于一次近似理论,采用弧坐标分量和Cartesian坐标分量共同描述柔性梁的变形场,并采用Green应变张量描述应变能,用Hamilton原理建立系统动力学方程,揭示产生动力刚化现象的力学本质。
3) quadratic approximation
二次近似
1.
Based on the quadratic approximation of the stability region boundary,this paper proposes a transient voltage stability margin index,and analyzes the transient voltage stability of a one-machine and one-load system including an electromechanical transient model of induction motor.
基于稳定域边界二次近似,提出了暂态电压稳定裕度指标,并分析了计及感应电动机机电暂态过程的单负荷无穷大系统的暂态电压稳定性。
2.
This paper presents a new transient stability index based on the implicit expression for the stability region boundary and an approximation of the proposed index based on the quadratic approximation of the stability region.
基于故障后电力系统稳定域边界的隐式方程,提出了隐式的暂态稳定指标,并利用稳定域的二次近似方法给出了该暂态稳定指标的一个近似估计。
3.
The CCT is determined by the crossing point of the quadratic approximation surface and the continuous faulted trajectory.
基于故障后电力系统稳定域边界的二次近似来估计临界切除时间。
4) first approximation
首次近似
1.
By using the methods of root-analysis for the characteristic equation and first approximation etc, this paper provides criterions of the asymptotic stability for the zero solution of the above meutioued delay difference equations.
运用特征根法及首次近似法等方法得到了上述两类方程零解渐近稳定的判别准则。
5) nearly subconvexlike
近次似凸
1.
In this paper,firstly we have introduced nearly subconvexlike set vaklued map and obtained a series of characterizations about it,lastly we give the proof of the equivalence of subconvexlike set valued map and nearly subconvexlike set valued map in linear topological spaces.
本文在线性拓补空间中 ,首先引进了近次似凸集值映概念 ,并获得了它的一些性质 ,最后我们给出了次似凸、近次似凸集值映射等价性的证明。
2.
The concept of nearly subconvexlike set-valued map is introduced and some important properties of the new concept are obtained in the linear space.
在线性空间中引入近次似凸集值映射概念,获得了它的一些重要性质。
6) high temperature approximation
高温近似
1.
A large body of conspicuous publications in recent years asserts that the high temperature approximation (HTA), a mostly tested and most widely used assumption in NMR spectroscopy and MRI technology, is invalid for concentrated samples in high magnetic fields such as for a proton COSY spectrum of water.
高温近似 (HTA)是NMR波谱学和MRI技术中久经考虑且应用最广的一个近似 。
补充资料：电力牵引高次谐波
电力牵引高次谐波
harmonics of electric traction
d Ionl一qlony旧gooe}x{ebo电j]牵引高次谐波(harmonies of eleetrietraction)整流式交流电力机车在整流过程中将引起交流侧电流、电压波形畸变，按傅立叶级数分析该畸变波形可分解成频率为基波频率整数倍的一系列高次谐波分量的叠加。 高次谐波电流、电压可引起下列不良影响: (1)对通信线产生杂音干扰影响; (2)引起电力系统中其他电力电容器设备的过负荷; (3)当电气化铁路负荷某次谐波电流频率与电力系统自身谐振频率相近时，可产生电流谐振，使该次谐波电流在电力系统中放大，危及电力系统安全运行; (4)使旋转电机、变压器、电力电缆的出力减少并产生过热，影响电气设备寿命; (5)造成继电保护误动或仪表读数误差; (6)使半导体开关元件换相失灵。 为限制谙波的危害，各国都规定了允许谐波含量的标准(见供电质童)。 为降低电力牵引负荷产生的谐波，在电力牵引变电所和电力机车中可装设由电容、电感组成的谐波吸收装置。交流一直流一交流电力机车利用电力电子技术，可实现低谐波分量的负荷特性，使谐波含量降低。
说明：补充资料仅用于学习参考，请勿用于其它任何用途。
参考词条