一阶

An ocean echo signal simulation system for verification and calibration of FMICW high frequency ground wave radar is presented in this paper.

该系统基于FMICW高频地波雷达的工作机理，以及一阶和二阶Bragg-Doppler谱的反演原理，利用直接数字合成的技术仿真出海洋雷达回波的模拟信号，以供雷达的校准与定标之用。

Aimed at the calculation complexity of Newton iterative method for solving nonlinear equation,a new iterative method with higher convergence rate and without derivative calculation is presented in this paper.Its convergence rate p is 1.839 and it doesn't need to calculate derivative.

为解决Newton迭代法求非线性方程数值解时必须提供一阶导数值的问题，提出了一个新的迭代方法，该方法不需提供导数值而只需计算函数值，且具有p=1.839的收敛阶，因而是一个收敛速度快且不需要计算导数值的迭代方法。

However, most of the existing projection methods are only first order or incompletely second order accuracy in time.

目前，绝大多数不可压缩数值方法，在时间方向上都仅仅停留在一阶或不完全的二阶精度。

The relationships between curvature and velocity fluctuating and between chord error and interpolation period in the Taylor expansion were given.

给出了一阶、二阶泰勒展开方法的速度波动与曲率的关系，弦误差与插补周期的关系。

Based on the interstices of yams, warp and weft crossed areas are located, and four textures of these areas are obtained by first-order and second-order statistics.

基于纱线间隙和经纬纱交叉区的存在，通过一阶和二阶的统计量可获取4种区域结构特征。

The objective of this paper is to evaluate various spatial interpolation methods, including ordinary Kriging, simple Kriging, lognormal Kriging, universal Kriging, disjunctive Kriging and inverse distance weighting interpolation for estimating soil surface Hg content with lognormal distribution, the linear and second-order polynomial trend, and t...

以分布类型为对数正态分布，同时具有一阶和二阶趋势效应的土壤重金属Hg为例，分别应用普通克立格法，简单克立格法，对数正态克立格法，泛克立格法，析取克立格法和距离反比权重法等 6种内插方法对其进行了估值，综合比较了各种内插方法的预测误差、统计特征值及插值结果分布图。

The permanent magnet synchronous motor is decoupled into second-order linear speed subsystem and first-order linear flux subsystem. The aim space voltage vector is ascertained by combining sector judgment of stator flux with the practical system inputs after linearization and decoupling. The system is decoupled into two linear subsystems, flux and rotor speed, which realizes the completely dynamic decoupling for permanent magnet synchronous motor speed control system.

将永磁同步电机动态解耦成二阶线性转速子系统和一阶线性磁链子系统，结合磁链扇区判断方法和线性化解耦后的实际系统输入来确定目标空间电压矢量，实现了永磁同步电机调速系统的转速和磁链动态解耦控制。

A decoupling control approach based on inverse system method had been applied for the permanent magnet synchronous motor, which was multi-variable, nonlinear and coupled system. PMSM was decoupled into second-order linear speed subsystem and first-order linear flux subsystem. The servo robust controller was used to design linear closed-loop controller for the pseudo-linear subsystems.

针对永磁同步电机这种多变量、非线性、强耦合的控制对象，应用逆系统方法，将永磁同步电机解耦成二阶线性转速子系统和一阶线性磁链子系统；在此基础上，采用鲁棒伺服控制器对伪线性子系统进行线性闭环控制设计。

Our method can solve the problem of local maximum in comparison with that using only mutual information. We also discussed the two-order mutual information.

为了使给出的结果更有说服力，分别讨论了一阶互信息和二阶互信息的情况，实验结果都证实了该方法的可行性。

When the flow of the river and the capability of the river diversion follow normal distribution or logarithmic Normal distribution or Pearson—Ⅲ distribution, the point estimation and the one order or two order approximately interval estimation of the risk probability of the criteria of river diversion are given.

并根据河道来流量和导流系统设计泄流能力分别服从正态分布、对数正态分布以及皮尔逊—Ⅲ型分布的分布形式，给出了施工导流标准风险率的点估计和一阶、二阶近似区间估计的计算公式。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。