查询词典 Boolean algebra

This passage analyzes the advantage and disadvantage of the Boolean Model and the Vector Space Model in information retrieval model: the Boolean Model is simple to realize, but its classification ability is limited and the logic expression formula is strict.

本文分析了信息检索中传统文档特征表示的布尔逻辑模型和向量空间模型的优缺点：布尔逻辑模型虽机制简单、容易实现，但是它的分类能力有限且逻辑表达式过于严格；向量空间模型将文档映射到连续域向量空间，为进一步的权重计算等多元处理提供了基础，但容易忽略文档集合中各个文档的一些共有特征。

Second, in the viewpoint of crypto analysis, the practical requirement for the cryptographic function is to construct the function that can resist all the known crypto analysis and attacks. In advanced, the main cryptographic properties are compared, and the relation among these cryptographic properties is analyzed, including the trade-off ones. Get the conclusion that the construction of cryptographic Boolean function is to find out the proper Boolean function in the whole vector space under the restriction of several cryptographic properties required for the security system.

然后本文从密码分析的角度，讨论了密码函数的实际需求，即构造能够抵抗已有密码分析与攻击的布尔函数；分析了布尔函数的主要的密码学性质，并比较了这些性质之间的相互关系，包括制约的关系；得出了构造布尔函数的实质的结论，即在向量空间中构造全体布尔函数，以所需的若干密码学性质作为限制条件，用有限域上的多项式、Walsh谱、Hadamard矩阵等数学工具找出适当的布尔函数用于加密体制的设计。

Ge__. These methods can return any value, but if the comparison operator is used in a Boolean context, the return value should be interpretable as a Boolean value, else a TypeError will be raised.

ge__。这些方法可以返回任何值，但是如果比较运算符用于布尔上下文，返回值应该被解释成布尔值，否则将抛出TypeError异常，通常0表示假， 1用于表示真。

Boolean - return a constant boolean, true or false.

布尔--返回一个常量布尔，真或假

The decomposition theorem becomes a bridge connecting fuzzy matrix theory with Boolean matrix theory, so we start this problem from Boolean matrix.

由于分解定理建立了模糊矩阵和布尔矩阵之间的桥梁，所以我们首先从布尔矩阵开始对这个问题展开研究。

On the other hand, it is expressible as a Boolean expression if you accept including function calls in the Boolean expression.

但换个角度，如果你允许在布尔表达式中植入包含函数调用，则它就是一个布尔表达式可表述的属性。

The Boolean has_key and the in and not in operators are Boolean, returning True if a dictionary has that key and False otherwise.

布尔类型的has_key 和 in 或 not in 操作符都是布尔类型的。如果字典中有该键就返回真，否则返回假。

False.译者:原文: The Boolean has_key and the in and not in operators are Boolean, returning True if a dictionary has that key and False otherwise.

修改为：对布尔类型的方法has_key和in 或 not in 操作符而言，如果字典中有该键，执行has_key方法、in或not in操作符会返回真，否则返回假。

Finally, the author proves the sharp bound for the indices of convergence of n*n reducible Boolean matrices with f〓≥2 the writer lets f〓 be the greatest common divisor of the distinct lengths of the elementary cycles of the associated digraph D (A for a reducible Boolean matrix A , and characterizes the matrices with the largest index.

最后，设f〓为可约布尔矩阵A的伴随有向图D的所有圈长的最大公约数，当f〓≥2时，我们得到了可约布尔矩阵幂敛指数的一个上界和达到最大幂敛指数的矩阵的完全刻划。

Based on the definition of Boolean function on set and positive extension, The sufficient and necessary condition of PBF is proven. At last, an algorithm of generating MSP expression of stack filter positive Boolean function is presented taking advantage of Hasse diagram.

通过定义布尔函数开、闭集和最小项正、负扩展，证明了布尔函数具有层叠性的充要条件是布尔函数开集的正扩展或闭集的负扩展具有不变性，在此基础上，提出了一种通过Hasse图确定层叠滤波器最简正布尔函数的算法。

Although translator has turned from being a crystal ball by which the original culture can unrestrainedly penetrate to another crystal ball by which the target culture can freely traverse, the translator's personal embodiment, in the process of cognitive act, are still absent in translation studies. Translators are still subjects without body or simply disembodied subjects.

译者虽然由原语文化可以自由穿透的玻璃球变成了译语文化可以自由穿越的玻璃球，但译者认知过程中的个体体验在翻译研究中依然缺席，译者依然仅仅是一个没有躯体体验的主体。

Chillingly, he claimed our technology is 'not nearly as sophisticated' as theirs and "had they been hostile", he warned 'we would be been gone by now'.

令人毛骨悚然的，他声称我们的技术是'并不那么复杂，像他们一样，和"如果他们敌意"，他警告说，'我们将现在已经过去了。