| In the face of endless security problems,relying on natural geographical conditions to form a strong sustainable development strategy has become an important direction of the study of geographical relations in various countries.In order to discuss the construction and application of geo-relational network,this paper establishes the mapping relationship between complex network and geo-relational network with the support of geographical thinking and geo-information technology,puts forward the general construction rules of geo-relational network,and forms the Terrestrial Adjacency Network,which is an example of geo-relational network model.Based on the land adjacent network,this paper makes a quantitative analysis of the geographical relationship of the network model from the aspects of nodes,structures and attributes.At the same time,in order to make the research closer to reality and further refine the network model,this paper discusses the geo-spatial structure of adjacent networks in Eurasia under different partition algorithms,studies the index changes under the dynamic evolution of the adjacent network model,and simulates the real world by using the objective laws and internal relations between the weighted features and the weighted features of the network.The research content has certain significance to the study of geographical relations.The main work and conclusions of this paper are as follows:(1)Based on the theory and method of geographical relationship and complex network,this paper probes into the general principles and methods of constructing geographical relationship network.With the help of complex network method,the georelational network data format is formulated,and the node data set and rule data set needed to generate the network model are established to form the general principles of network model construction.The process is as follows: get the vector data of the world’s land countries,extract the geographic center through geographic information tools,build the system rule data set,select the corresponding nodes from the node database according to the requirements and specify the rule constraints to generate the georelationship network model,and finally,use the network analysis tools to visualize the model and calculate the indicators.(2)This paper constructs the land adjacent network,analyzes the geographical relations of the elements and characteristic indexes of the land adjacent network,and calculates and compares the characteristics of the three global land adjacent networks.From the perspective of inclusion relationship,geo-relational network is the application of complex network in geo-relational field,and land adjacent network is one of the examples of geo-relational network.The enlightenment is as follows: for different regional adjacent networks,in terms of network structure characteristics,Eurasian land adjacent networks have scale-free characteristics,while African and American land adjacent networks do not have scale-free characteristics;The spatial structure of Eurasia contiguous network is non-uniform due to scale-free characteristics,and the geo-spatial structure shows "core-edge" distribution.In terms of node indicators,the distribution of different indicators in Europe,Asia,Africa and America shows different characteristics,and the distribution of network indicators in America is relatively single compared with that in Europe and Asia.In terms of network structure,the comprehensive quality of network structure in Africa is high,with high transmission and low heterogeneity.Different regions have similar distribution rules in spatial clustering,for example,high and low clustering of cluster coefficients often appear in coastal countries;In terms of spatial distribution,on the whole,the junction of Europe,Asia and Africa is the richest.(3)Focusing on the Eurasian land adjacent network,this paper studies its geospatial structure from the aspects of geo-spatial community,network evolution and land accessibility.As for the division of geo-spatial societies,the resolution is 0.662,the number of societies is 6,and the societies are roughly distributed in Western Europe,Central Europe,Northern Europe,Caucasus,Middle East and East Asia.In the analysis of k-nuclear network,the network associations with Germany,Iran,China,Russia and Turkey as the outer ring of the network structure and Armenia,Azerbaijan and Central Asia as the inner ring are obtained.Self-network associations in France,Germany,Ukraine,Russia,China,South Korea,Turkey and Iran show different structural characteristics in geographical adjacent networks in three aspects: region,direction and shape.In terms of network model evolution,taking the conflict between Afghanistan and Russia and Ukraine as an example,this paper simulates the network evolution model based on points and edges and the network evolution model based on edges in complex networks,and analyzes the changing characteristics of indicators of neighboring countries.It is found that the network is more affected by "node failure" than "edge failure",but "edge failure" is more targeted.In terms of land accessibility,different attributes are superimposed on the network model,and a geometric topological network,a spatial distance network and a network with traffic attributes based on weighted network,single attribute network and comprehensive attribute network are constructed in Eurasia.The results show that: for the geometric topological network,the cluster coefficient and the shortest path of national nodes are calculated,and it is found that it has the characteristics of small world;Compared with the geometric topology network,the spatial distance network takes distance as the cost factor,which can provide a more realistic geographical relationship.By superimposing the data of roads,railways,territorial areas,node proximity centrality,node intermediary centrality,etc.in Europe and Asia,the land adjacency network with attributes is constructed,and it is recognized that France,Germany,Poland and Austria have strong land accessibility.On the whole,the land communication ability in Europe is higher than that in Asia.Finally,taking China as a starting point,this paper makes use of the path comparison of different network models to provide suggestions for the "facilities connectivity" of "the Belt and Road initiative" at the level of land communication. |
