必要条件

According to relation conjunctions reflects, conditionals can be divided into three types: hypothetical compound sentence, conditional compound sentence and unconditional sentence; According to whether the content of is objective or not, conditionals are types as indicative conditionals and counterfactual conditionals.

根据关联词语所反映的是充分条件关系还是必要条件关系，可分为假设复句、条件复句以及五条件句；根据条件句前件与后件的内容是否实现，可分为直陈条件句与反事实条件句。

This paper introduces the sufficient conditions of the similarity between someparticular block matrix on the division rings.

给出除环上某些特殊块阵的相似的充分条件，并具体给出了对于除环上n阶阵A和B，AB与BA的群逆都存在的充分必要条件，并推广了Cao等人"在两个矩阵乘积群逆的逆序法则"文章中一个结论。

The similarity conditions of geometry, flow movement and dynamics of air bubbles are analyzed.

从气体运动状态方程出发，研究了竖井有压流动模型中气水两相流的运动规律，分析了气泡几何相似、运动相似以及动力相似的条件，指出掺气浓度相似律是研究气水两相流相似问题的又一必要条件，即原、模型的掺气浓度必须相等，前提为大气压强或密度相似。

To this end, the equations of motion of the full-size flat plate and its scale model are discussed first to determine the conditions for the dynamic similarity of the last two models.

为了达到上述目的，本文首先探讨原型与缩小平板在承受集中负荷时的运动方程式，以决定两系统间之动态特性相似的必要条件。

In the preceding example, womanhood and the right royal lineage are each individually necessary conditions for princesshood and conjointly they comprise a sufficient condition for princesshood.

在这个例子中，女人身份和合法的皇家血统，各自是公主身份的必要条件，合起来就构成公主身份的充分条件。

Moreover, the smallest degree sum on potentially K(p,1,1)-graphic sequences and k-cycle-graphic sequences are given respectively; bounds on m-restricted edge connectively and 3,4-restricted edge cut of graphs are also characterized respectively.

此外，还分别给出了蕴含k圈和（p，1，1）-部图可图序列度和的下界；分别给出连通图含m-限制边割的充分条件和必要条件及连通度的界。

By giving the example, explains that theorem 4 in the refuted paper is not the necessary condition of the continued fraction convergences, by discussing the indeterminacy of the lever function and citing the counterexamples, expounds that the theorem 4 is not sufficient condition of the parameters W and W -1 neutralizing each other, and so shows algorithm 1 and 2 in the refuted paper to be incorrect.

通过举例说明了"攻文"定理4不是连分式收敛项的必要条件，并通过对杠杆函数不确定性的讨论和反例的举证说明了"攻文"定理4不是W与W –1相互抵消的充分条件，从而证明了"攻文"算法1和2及其衍生方法是错误的。

We see the same thing, watching moment by moment the movement of historical personages (that is, restoring the inevitable condition under which all action takes place—the condition of the continuity of motion in time), and not losing sight of the necessary connection of historical figures with the masses.

假如我们每时每刻注视历史人物的运动（就是恢复所发生一切的必要条件——运动在时间上的连续性），不疏忽历史人物和群众的必要联系，我们就会看见同样的情况。

Secondly, based on the Mawhin's continuity theorem in coincidence degree theory and the Brousk's theorem, some novel criteron of the existence on periodic solutions are obtained under the more generalized assumptions than before.

主要工作是：第一，应用构造Liapunov函数以及Lasalle不变性原理，给出了解的有界性与收敛性的一些新的充分条件和充分必要条件，这些结果包含或扩展了已有文献关于同样问题的一些重要结果。

This article uses the implicit function theorem and the properties of analytic functions,with less limitations for the uniqueness,continuity,continuous differentiability of the implicit functions,and gets the sufficient and necessary conditions of the existence of implicit functions by simplifying them.

从常用隐函数存在性定理出发，放宽对隐函数唯一、连续、连续可微等性质的限制，利用解析函数的性质将其展拓，得到广义隐函数存在的充分必要条件和广义隐函数的分布特征。

Since historical times,England ,where the early inhabitants were Celts, has been conquered three times .

从有历史以来，英国，在此地早期居住的是凯尔特人，已经被征服了三次。

Bluetooth OBEX File Transfer Enables the sending and receiving of files on your phone via Bluetooth.

蓝牙OBEX文件移动允许经过蓝牙传送和接受文件。。。。