In information theory, "information" is regarded as knowledge which reduces or removes(71) about the occurrence of a specific ev

admin2010-01-23  27

问题 In information theory, "information" is regarded as knowledge which reduces or removes(71) about the occurrence of a specific event from a given set of possible events. The concept "event" is to be understood as used in the theory of probability. For instance, an event may be the occurrence of a(72) character or word in a given message or in a given position of a message.In communication theory, channel is defined as that part of a communication system that connects the message source with the message sink. An encoder may be inserted between the message source and the input to the channel, and a(73) between the output of the channel and the message sink. Generally, these two units are not considered as being parts of the channel. In certain cases, however, they may be considered as pans of the message source and message sink,(74) In information theory(75) to Shannon, the channel can be characterized by the set of conditional probabilities of occurrence of all the messages received at the message sink when a given message emanates from the message source.

选项 A、based
B、following
C、according
D、subject

答案C

解析 在信息论中,将“信息”看作在可能事件的给定集合中,减少或去除某一特定事件出现的不确定性的知识。“事件”这一概念按概率论中的用法来理解。例如,事件可以是在给定消息中或在消息的给定位置上,某一特定字符或字的出现。在通信论中,将信道定义为通信系统中连接消息源与消息汇的那一部分。在消息源与信道输入之间可插入一个编码器,在信道输出与消息汇之间可插入一个译码器。一般认为,这两种器件都不是信道的组成部分。不过在某些情况下,可将其分别看作消息源与消息汇的组成部分。按照香农所提出的信息论,可将信道表征为:当从消息源发出某一给定消息时,在消息汇处收到所有消息出现的条件概率的集合。
转载请注明原文地址:https://kaotiyun.com/show/DcxZ777K
0

相关试题推荐
随机试题
最新回复(0)