Study On Cascading Invulnerability Of Logistics Support Networks

Due to the evolution of modern battle styles, especially the local warfare after 90's of last century, logistic support networks become more and more important, and the ability and quality of logistic support become key factors that decide the success of modern battles. At the same time, the logistic support networks are the focus of attack and defense. Consequently, study on invulnerability of logistic support networks is of great theoretical and practical significance.The invulnerability of logistic support networks is decided by not only network topology, but also network load. When one vertex fails, its loads will be directed to other normal vertices, which will then fail and cause further load redistributions if the new loads exceed their capacities. This dependent failure behavior is called"cascading failure"and the invulnerability considering cascading failure is called"cascading invulnerability". Guided by complex network theory, this dissertation studies thoroughly and systematically the modeling, analysis, optimization and application of cascading invulnerability of logistic support networks using methods of graph theory, statistical physics, operations research, probability theory and computer simulation. The main results and contributions of this dissertation are as follows.1) A cascading invulnerability model for logistic support networks is proposed.The essence of cascading failure is a dependent failure based on load. The factors that effect cascading failure include: topology, load and cascading process. By analyzing the characteristics of logistic support networks, a network model, a load model and a cascading invulnerability model for logistic support networks are proposed respectively. Based on structure and function, logistic support networks are divided into the strategic logistic support networks and the tactical logistic support networks. The strategic logistic support networks are modeled as spatial networks, the tactical logistic support networks modeled as uniform random networks, and the loads are modeled as logistic networks. After analyzing the cascading failure process on logistic support networks, the route strategy, load redistribution rule, failure form and measurement of cascading invulnerability are presented. Finally, a cascading invulnerability model for logistic support networks is proposed.2) The cascading invulnerability of tactical logistic support networks with typical distributions of capacity is studied analytically.The distribution of capacity is the most key factor that affects the cascading invulnerability of tactical logistic support networks. The cascading invulnerability with three typical distributions of capacity is studied analytically using the generating function and branching process methods, i.e., uniform capacity, random capacity and property-related capacity. The results show that there is a critical capacity for all three typical distributions of capacity. Above the critical capacity, large scale cascading failures occur; under the critical capacity, large scale cascading failures do not occur. The numerical simulations verify the validity of our analytical results.3) The cascading invulnerability of strategic logistic support networks with task constraints is studied using the numerical simulation methods.There are both civil transport loads and military support loads on strategic logistic support networks. Moreover, the vertex loads at different spatial locations are different at the same time, and the load of same vertex at different time is dynamic. Hereby, the task constraints are divided into the task space constraints and the task time constraints. The cascading invulnerability of strategic logistic support networks with the task space constraints and the task time constraints are studied respectively. The results show that the cascading invulnerability of strategic logistic support networks has remarkable difference under different task constraints. The reasons for the difference are revealed thoroughly.4) A software system for analysis of cascading invulnerability of logistic support networks is implemented.A software system for analysis of cascading invulnerability of logistic support networks is implemented as a platform, on which the logistic support tasks can be imported and edited; the loads and capacities of vertices can be set. Using the software system, the cascading invulnerability of logistic support networks can be analyzed with our models and methods.