必要条件

Attempted analyses of concepts in terms of necessary and sufficient conditions, even where they fail, abet discovery.

试图从必要条件和充分条件的角度来分析概念，即便失败了，也能有所发现。

On the whole, we do as follows: Firstly, we list some conceptions and lemmas for later use. Secondly, we inducted the absolute value norm in the two-dimensional vector interspace, and also proved the two-dimensional vector interspace is a Banach Interspace. Thirdly, we define two-dimensional vector-valued functions on a interval by the definition of -fine partitions in part 1. Then, some sufficient and necessary conditions of integrabel are given, and discuss the property of the integral on two-dimensional vector-valued functions.

主要包括以下内容：在第一部分，我们介绍了本文所用到的几个基本概念和引理；第二部分，我们在二维向量空间中引入了绝对值范数，并且证明了二维向量空间是一个Banach空间；在第三部分中，通过第一部分关于-精细分划的定义，我们给出了在某区间上二维向量值函数积分的定义以及可积的充分必要条件，并讨论了二维向量值函数积分的一些性质。

In this thesis, absolute stability of Lurie control systems is studied.

中文摘要：这篇硕士论文研究了型控制系统绝对稳定问题，重点讨论判定其零解绝对稳定的几种常用的方法，得到了绝对稳定的一些充分必要条件或充分条件及代数判据。

Therefore, accessibility of source code is a necessary condition for free software.

因此，能够接触源代码是自由软件的必要条件之一。

Fourthly, based onour experiments and the literatures', the necessities of endohedralmetallofullerenes' formation are the existence of well graphitized of carbonand metal acetylide.

四在实验和文献报导的基础上，提出原料中完好石墨化的碳和电石型金属碳化物的存在是形成Fullerene笼内金属包合物的必要条件。

In addition, sVCAM-1 induced cell shape change and actin polymerization, which are necessary for cell movement.

此外，sVCAM-1能诱导细胞形态的改变和肌动蛋白的聚合，这些都是细胞运动的必要条件。

In 1961 they published the first carrier will be injected into the semiconductor PN junction to achieve the "injection laser" exposition and demonstration in the tunnel diodes as high as in Jane and the PN junction to achieve population inversion (which is Produced by stimulated emission of the necessary conditions for) the possibility, but also that active high-density areas around the most active carrier of the border areas on both sides of the refractive index of a difference, creating optical waveguide effect.

他们又于1961年最先公开发表将载流子注入半导体PN结以实现"注入激光器"的论述，并论证了在如隧道二极管中那样高度简并的PN结中实现粒子数反转(这是产生受激发射的必要条件)的可能性，而且还认为有源区周围高密度的多数载流子造成有源区边界两边的折射率有一差值，因而产生光波导效应。

FM area of the ring reward FM and at any time can update the properties of the additional equipment is a necessary condition for strengthening the tanks.

FM方面奖励的戒指FM和随时可以为更新装备附加的属性也是强化坦克的必要条件。

It is proved that null-null additivity is equivalent to pseudometric generating property for a finite fuzzy measure on S-compact space.

证明了在S紧空间上的一个有限模糊测度是零-零可加的充分必要条件是它有伪距离生成性质。

In this paper, the adjointness of the product of two differential operators generated by a third order normal and singular symmetric differential expression in the limit-circle case is discussed. The necessary and sufficient conditions which make the product operators being the adjoint operators obtained by the matrix analysis and calculation. At the same time, the adjointness of the product of the power and adjointness operator obtained.

本文首先讨论了正则和奇异两种情况下两个极限圆型三阶对称微分算式生成的微分算子的乘积的自共轭性，运用矩阵分析和计算，得到了乘积算子为自共轭算子时边界应满足的充分必要条件，同时得到了幂算子的自共轭性、自共轭算子乘积的自共轭性等乘积算子的其它若干性质。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。