文档介绍：摘要
现实世界中,存在大量的复杂系统可以用复杂网络来表示,例如,互联网、航空网、新陈代谢网、演员合作网等,即在网络图中点表示个体,边表示个体之间的相互联系。在网络图中,这些不同类型系统的拓扑结构有着纷繁复杂的表现,但同时又表现出一般的3大共性:连接度呈幂率分布,较高的集聚系数、以及较短的平均路径。这些共性引起了科学工作者的极大兴趣,并引起了复杂网络的研究浪潮。本文针对物流网络的特征,将复杂网络研究中的演化模型、数学解析方法、计算机仿真方法应用到物流网络中,通过建立改进的复杂网络模型来对物流网络的宏观拓扑结构进行研究。
本文首先介绍了复杂网络研究背景和意义以及物流配送中心选址问题的现状,并将复杂网络所涉及的基本概念做了较为详细地解释。然后通过对物流网络的分析,发现物流网络呈现出结点数量多,联系复杂,择优连接等复杂网络的特征。本文基于经典的复杂网络BA模型,引入老节点之间的择优连接机制,建立了一类变幂率的物流网络模型,通过解析结果和计算机模拟证明了在模型的两个参数的调控下,其幂指数仍然介于[2,3]之间,说明了物流网络是一种特殊的复杂网络。
接着,本文对物流网络的演化模型进行了计算机模拟,计算出其物流网络节点的连接度分布呈幂率分布,并选取网络中度极大的若干节点作为物流网络的拟建节点。将拟建节点的相关数据作为双层规划模型的输入,由此可以计算出物流选址最优方案。
本文最后根据实际企业建设物流配送中心的具体案例,以企业已建物流中心和分销点为基础,模拟生成具有一万个带有地理坐标的节点的物流网络,计算每个节点的连通度,并选取度较大的三个节点作为拟建物流中心节点。接着将此三个节点的相关数据代入双层规划模型进行计算分析以得出最终选址结果。基于复杂网络的双层规划模型为物流网络配送中心选址提供了一个新的思路。
关键字:复杂网络,物流网络,物流选址,复杂系统,双层规划
ABSTRACT
In the real world, there are many systems, which can be represented works, such as the , work, work,movie actor work, and so on. In works, the nodes represent individuals anizations and edges mimic the interactions among them. And many empirical studies indicate that these various kinds works have mon characteristics: power-law distribution of degree, high clustering coefficient, and small average path length. These characteristics have received researchers’ great interest and considerable attention. On account of the characteristics of work, this thesis takes mathematic analytical method puter simulation into the work, builds some improved models on the work to study on the character of the work.
Firstly, this thesis introduces the background and significance of works and logistics; also, relevant conceptions are explained in a detailed way. Then to solve the limitation of the models bine the work, the study works as follows:
1. The location of work Nodal Points with the characteristics work is proposed. Based on work, concept of the impact factor is introduced, the statistical characteristics are considered as factors that determine the degree of the influence between the log