一阶

In this thesis, we design and construct a low-level servo control system for a biped walking robot.

中文摘要本论文实际设计制作一双足机器人十二关节轴的低阶伺服控制系统。

The existing enterprises in China, which are no more than twenties years old, suffer all kinds of birth pangs consisting of the reformation of system and the conversion of economy.

中国真正意义上的企业存在的时间不过是改革开放后的短短二十几年，在这一特定历史阶段里，中国企业承受了体制改革，经济转轨等带来的种种阵痛。

In this paper, we propose a new visual cryptographic method for gray-level and chromatic images without pixel expansion. We simultaneously encrypt m successive pixels (called an "encryption sequence") each time in accordance with two basis matrices. In every m encryption sequences with b blacks, we make sure that b encryption sequences are encoded by black basis matrix, and the other ones are encoded by white basis matrix.

本研究提出一种不需要像素扩展的灰阶和彩色视觉密码的技术；我们的方法利用多点同时加密的概念，每次取连续的 m 个点做为加密序列进行加密，我们的方法可以确保在 m 个具有 b 个黑点的加密序列中，一定会有 b 个加密序列是使用黑点基础矩阵加密，另外的个则使用白点基础矩阵加密，因此在叠合影像上黑与白的变化很规律。

In Chapter 2 of this thesis,we show that the rate of convergence to equilibrium is Ot~(-∞,by using a method developed for the Boltzmann equation without external force in.

在本论文的第二章，通过使用对无外力的Boltzmann方程进行证明的一种方法，我们证明了VPB系统以近似指数阶的速度Ot~(-∞收敛到全局Maxwellian状态。

The second order nonlinear optical behaviors of a new borate crystal BiB3O6 were studied in terms of chemical bond viewpoint.

利用化学键的观点，研究了一种新型硼酸盐晶体BiB3O6的二阶非线性光学行为。

Firstly, some fundamental knowledge, such as the describing of laser field, the Kind of electron-atom scattering in a laser field, and so on, are introduced. Then a compution method which is called the Second-order Born approximation and is used to calculate the cross section of electron-atom scattering in a laser field, is provided.

本文首先介绍了激光场的描述、激光场中电子—原子散射的分类等相关理论，接着详细描述了一种计算激光场中电子—原子散射截面的方法——二阶玻恩近似理论。

Applied Green's function, the differential equations will be transformed into the equivalent of integral equations, sufficient conditions for existence and uniqueness of positive solutions for fourth-order nonlinear singular continuous boundary value problems with p-Lapacian operator are obtained.

文中，利用格林函数，将微分方程转化成等价解的积分方程，给出了该奇异非线性四阶p-Lapacian微分方程边值问题的正解的存在及惟一性的一个充要条件。

The boundary conditions at the free surface and body are satified to the second order at each time step.

一、二阶问题分别满足各自的自由表面条件和物面条件。

The use of these techniques to study for these kinds of third-order boundary value problems seems to be new.

结果表明，这种技巧为其它三阶边值问题的研究提出了一种新的思路。

A second order accurate, high resolution scheme, called WSUC scheme, has been proposed. This scheme is total variation bounded and unconditionally stable in the sense of convective numeral stability.

提出了一种具有二阶空间精度的WSUC格式，对它的精度、总变差有界性和对流的数值稳定性进行了分析。

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。