多种群并行进化神经网络的研究及应用
林丽莉1 冯天瑾1 周文晖2 郑宏伟3
(1 青岛海洋大学电子工程系,青岛,266003)(2 中国计量学院自动化系,杭州,310034)
(3 颐中烟草(集团)技术中心开发二室,青岛,266021)
摘 要 提出一种新的多种群并行遗传算法 (NMPGA),并将其作为多层前馈神经网络 (MFNNs) 的学习算法,从而形成一类新的MFNN模型——多种群并行进化神经网络 (MPENNs)。首先,对一给定的网络结构,随机产生一初始权重的集合,这个集合实际上对应着一组具有相同结构但不同权重的神经网络。然后,采用NMPGA 对MFNNs 的权重进行进化。最后,性能最好的网络被选作目标问题的解。在NMPGA算法中,作者采用浮点数编码来克服传统二进制编码的精度不足问题,并设计了专门的杂交算子和变异算子来增强算法性能。实验结果表明,MPENNs能成功解决异或问题、三元奇偶问题及成品烟的感官质量评价问题。
关键词 多层前馈神经网络(MFNNs);多种群并行遗传算法(MPGA);多种群并行进化神经网络(MPENNs);浮点数编码
中图法分类号 TP3-05 文章编号 1001-1862(2002)02-312-07
Research and Application on Multigroup Parallel Evolutionary Neural Network
Lin Lili1 Feng Tianjin1 Zhou Wenhui2 Zheng Hongwei3
(1 Department of Electrical Engineering, Ocean University of Qingdao, Qingdao 266071, China)
(2 Department of Autocontrol Engineering, China Institute of Metrology, HangZhou 310034, China)
(3 Second Development Team of Technology Center, Etsong Tobacco (Group) Co., LTD, Qingdao 266021, China)
Abstract A novel multigroup parallel genetic algorithm (NMPGA) is presented as a learning method for multilayer feedforward neural networks (MFNN). Consequently, a new MFNN model multigroup parallel evolutionary neural network (MPENN) is formed. First, for a given network, architecture initial weight sets are generated randomly, which in fact are corresponding to a group of MFNN with the same architecture but different weights. Then the NMPGA is adopted to evolve the weights and biases of all the MFNN. In the end the best network is chosen as a solution to the object problem. In addition, float encoding is introduced to solve the accuracy insufficiency problem of the traditional binary encoding. Furthermore a new crossover operator and a new mutation operator are devised to enhance the algorithm performance. The experimental results show that MPENN can solve the XOR problem, the 3-bit parity problem and the sensoryquality assessment of cigarettes successfully.
Key words multilayer feedforward neural network; multigroup parallel genetic algorithm; multigroup parallel evolutionary neural network; float encoding



