【作者】 李冰；

【导师】 孙德宝；

【作者基本信息】 华中科技大学 ， 控制理论与控制工程， 2005， 硕士

【摘要】 手写体字符识别是模式识别中一个非常重要和活跃的研究领域,字符识别不是一项孤立的技术,它所涉及的问题是模式识别的其他领域都无法回避的; 应用上,作为一种信息处理手段,字符识别有广阔的应用背景和巨大的市场需求。因此,字符识别的研究具有理论和应用的双重意义。人工神经网络识别方法是近年该研究领域的一种新方法,该方法具有一些传统技术所没有的优点:良好的容错能力、分类能力强、并行处理和自学习能力,并且是离线训练和在线识别。这些优点使它在手写体字符的识别中能对大量数据进行快速实时处理,并达到良好的识别效果。由于手写体字符的识别(特别是手写体数字识别)要求系统必须具有很高的识别率和可靠性,而这两者又往往是难以兼顾,针对这一情况本文建立了一种用于手写体字符识别的三级神经网络模型。在该模型中,各个子神经网络分别与不同的具有互补性的图像特征提取方法相结合; 识别时,三个神经网络先串联再并联,利用拒绝机制和投票机制进行协作识别。该模型充分有效的利用了各种特征信息,从实验结果看,也达到了较好的辩识目的。本文按照该多级识别系统的建立过程依次介绍了字符图像的预处理、字符特征提取、神经网络及其优化算法以及多神经网络的集成,文章最后根据给出识别系统在Matlab 平台上的实验结果比较讨论了识别系统的性能、分析了建立该识别系统的注意事项。更多还原

【Abstract】 Handwritten character recognition is a very important and active research in pattern recognition. Theoretically, it is not an isolated technique. It concerns with the problem that all the other areas of pattern recognition must confronted; Practically, being a kind of information processing measure, character recognition has a very broad application background and vast need of market. Thus, it is of both theoretical and practical significance. Artificial neural network recognition method is a new method of the research field in recent years, and this method has some merit that traditional technique do not have; good tolerance for error, strong sorting ability, strong parallel handling ability and strong self-learning ability as well as its off-line training and on-line recognizing. All these merits contribute its perfect performance in handling vast data set and handling in timely manner. The characteristics of handwritten character set(especially the numeral set) demand the recognition system take account of both high accuracy and reliability. It is very difficult to give considerations to both of them. To deal with this problem, three complement classifiers are given and their recognition results are combined by the proposed integration method. In this system, different network is combined to different feature extraction. Multiple neural networks collaborate perfectly to make full use of features so that give us satisfying results. This paper mainly involves preconditioning and feature extraction of handwritten character picture, the main theory of neural network, and training of recognition system of neural network.更多还原