相比于其他交通模式，航空网络具有高效灵活的优势，但同时其空间结构也更为复杂。本项目拟研究民用航空网络中节点(即机场)间的一种特殊关系：可替代关系。存在可替代关系的节点组合具有这样的特点：当组合中部分节点受到破坏时（由于自然或人为因素导致机场关闭或者容量下降），其他完好的节点可以代为承载被破坏节点上的原有负荷，使得网络的整体性能变化不大；而当组合内的所有节点都遭到破坏时，没有其他节点可以承载这些负荷，整个网络的性能会出现突变。初步研究发现，可替代关系广泛地存在于航空网络中，呈现出非常复杂的分布，其对航空网络的结构与性能具有重要影响。本项目拟对航空网络中的可替代关系开展研究，基于鉴定和量化结果，探究其对网络可靠性与鲁棒性的影响。进一步地，探索如何利用可替代关系对当前的航空网络进行结构优化。本项目旨在为理解和改进航空网络以及广义复杂网络提供一个新的角度，具有重要学术意义和应用价值。

Compared with other transportation modes, the air transport network has the advantages of high efficiency and flexibility, while its spatial structure is also more complicated. This project intends to study a special relationship between nodes, i.e. airports, in the civil air transport network: alternative relations. The nodes in an alternative group have the following characteristics. When some nodes in the group are damaged (the airport is closed or its capacity is reduced due to natural or human factors), other intact nodes can carry the original load on the damaged node. As a result, the overall performance of the network does not change much. However, if all nodes in a alternative group are damaged, no other nodes can carry these loads, and the performance of the entire network will decrease largely. Alternative relations exist widely in air transport networks, presenting a very complex distribution, which has an important impact on the structure and performance of air transport networks. This project intends to conduct research on alternative relations in air transport networks, and explore its impact on network reliability and robustness. Further, alternative relations will be used to optimize the structure of the current air transport network. This project aims to provide a new perspective for understanding and improving air transport networks and generalized complex networks. It has important academic significance and application value.