排序方式: 共有29条查询结果,搜索用时 54 毫秒
21.
Amir-R. Khorsand 《Journal of The Franklin Institute》2007,344(5):595-612
Evolutionary structural design has been the topic of much recent research; however, such designs are usually hampered by the time-consuming stage of prototype evaluations using standard finite element analysis (FEA). Replacing the time-consuming FEA by neural network approximations may be a computationally efficient alternative, but the error in such approximation may misguide the optimization procedure. In this paper, a multi-objective meta-level (MOML) soft computing-based evolutionary scheme is proposed that aims to strike a balance between accuracy vs. computational efficiency and exploration vs. exploitation. The neural network (NN) is used here as a pre-filter when fitness is estimated to be of lesser significance while the standard FEA is used for solutions that may be optimal in their current population. Furthermore, a fuzzy controller updates parameters of the genetic algorithm (GA) in order to balance exploitation vs. exploration in the search process, and the multi-objective GA optimizes parameters of the membership functions in the fuzzy controller. The algorithm is first optimized on two benchmark problems, i.e. a 2-D Truss frame and an airplane wing. General applicability of the resulting optimization algorithm is then tested on two other benchmark problems, i.e. a 3-layer composite beam and a piezoelectric bimorph beam. Performance of the proposed algorithm is compared with several other competing algorithms, i.e. a fuzzy-GA-NN, a GA-NN, as well as a simple GA that only uses only FEA, in terms of both computational efficiency and accuracy. Statistical analysis indicates the superiority as well as robustness of the above approach as compared with the other optimization algorithms. Specifically, the proposed approach finds better structural designs more consistently while being computationally more efficient. 相似文献
22.
大量而频繁的读者流失导致了图书馆知识服务范围的减少,降低了图书馆信息服务的质量。本文根据读者资料和借阅行为及其相关数据等历史信息,将径向基神经网络应用于读者流失分析中,针对目前图书借阅中存在的问题,给出了读者流失预测模型,利用训练后的模型对读者的流失率进行预测并生成读者列表。该模型通过试验运行,取得了良好的效果,对大学图书馆的服务策略实施具有现实的指导意义。 相似文献
23.
吴晓君 《湖南科技学院学报》2006,27(1):157-159
"NN"类名词由多个相关的名词性语素组成,名词性语素之间的关系具有复杂性,即"NN"之间有修饰关系、类属关系、同义关系等.这类名词与量词的搭配是否合理,与各自的语义特点和名词内部的结构有关,有很强的双向选择性.随着社会发展,这类名词越来越多,应重视这类词的语法特点. 相似文献
24.
J. David Midyette Andrew Youngkin Sheila Snow-Croft 《Medical reference services quarterly》2013,32(1):39-50
The use of social media is ubiquitous in the daily lives of nearly three quarters of the population in the United States. This article addresses the process and results of a policy development project for a National Network of Libraries of Medicine Regional Medical Library. Content, scheduling, editing, and author responsibilities are addressed for each of the chosen media outlets, as well as the preparation of prefatory material using an online social media policy development tool. 相似文献
25.
26.
27.
28.
阿布都热衣木·热西丁 《和田师范专科学校学报》2010,29(5):184-185
本文提出使用Gabor小滤提取维吾尔文笔迹的纹理特征方法。首先,通过预处理形成维吾尔文纹理图像。按照维吾尔文笔迹的特点,对Gabor滤波器进行改进。然后用一组Gabor滤波,过滤后获得图像的高维特征向量。最后,最邻近分类器(NN)分类器对不同17名人的维吾尔文笔迹样本进行分类实验,并获得79.8%的鉴别率。 相似文献
29.