摘要
Internet物理特征量短期及长期预测是一个重要课题,为此,首先定义了加权Internet网络,然后形式化定义表征加权Internet的物理参量———加权Internet访问直径,接下来根据海量数据变化特点,提出了基于Logistic模型的、以正余弦函数模拟振荡变化的数学模型,使用浮点型遗传算法分别进行拟合实验,并通过实验结果对上述模型进行了评价和选优·由于加权访问直径演化极为复杂,传统的一维数学模型在长期预测中已不适用·因此,在长期预测方面,首先计算得到加权Internet访问直径的关联维数,证实其演化过程为混沌现象,存在奇异吸引子·最后根据关联维数及奇异吸引子相近空间混沌轨道运动特性,提出了基于四维微分方程组的加权访问直径长期预测的形式模型·
Physical properties of Internet are discussed in this paper. Based on giant samples, weighted Internet is firstly defined, a physical property of weighted lnternet-weighted traveling diameter-is defined. And then according to features of samples, a model is put foreword. The model includes two parts ： one part is logistic model, which simulates the development of traveling diameter, and the other part is sine and cosine functions, which simulates the oscillation during the development of traveling diameter. Since the development of weighted traveling diameter is very complex, the model proposed in this paper is far from suitable while being used for a long-term forecast. To solve the problem of long-term forecast, correlation dimension of weighted traveling diameter is firstly calculated, which proves that the development of weighted Internet traveling diameter is a phenomenon of chaos and a strange attractor exists. Finally, based on correlation dimension and properties of chaos path near the strange attractor, a model of four-dimension function group is put foreword, which is comparatively suitable for a long-term forecast.
出处
《计算机研究与发展》
EI
CSCD
北大核心
2006年第6期1027-1035,共9页
Journal of Computer Research and Development
基金
国家"八六三"高技术研究发展计划基金项目(2001AA415320)~~
