Causal Consistency Operation Modeling Of Multi Granularity Spatiotemporal Objects Based On Graph Model

Geographic information modeling is experiencing a shift from traditional geometry-oriented and object-oriented to multi-granularity spatio-temporal object modeling.Multi-granularity spatio-temporal objects achieve a more comprehensive description of geographic objects by describing spatio-temporal reference,spatiotemporal location,spatial morphology,attribute characteristics,composition structure,association relationships,behavioral capabilities and cognitive capabilities.At the same time,multi-grain spatio-temporal objects have complex characteristics such as multilevel nesting,multi-elements,multi-scales,and multi-associations,and their descriptions are entity objectified and networked data expressions.This complex spatial data structure makes it possible to carry out collaborative workflow processing,where different operation choices and user's operation preferences often lead to data conflicts,resulting in final causal inconsistency.That is,the final result data obtained under different editing or operation sequences are inconsistent.In this paper,we conduct a research on the causal consistency of multi-grained spatio-temporal objects based on graph model for the problem of causal consistency in collaborative operations of multigrained spatio-temporal objects,and the main contents and results are as follows:(1)Realizes the multi-grain spatio-temporal object representation and its operation rules construction based on graph model.The multi-granularity spatiotemporal objects are expressed by nodes and the relationships between objects are expressed by edges,which together form an object undirected graph;the regular operation methods of multi-granularity spatio-temporal objects are refined and subdivided,and seven basic operators of object operations are defined;on this basis,the graph model is used to describe the operations of objects,and the graph model representation of object operation process is realized,which lays the foundation for collaborative operations based on multi-granularity spatio-temporal objects.(2)A theoretical model of causal consistency of multi-grain spatio-temporal object operations and an operation graph construction method are proposed.Based on the operation rules of multi-grain spatio-temporal objects,the global and local causal consistency of the operation graph of multi-grain spatio-temporal objects is defined.The set of operation rules of multi-grain spatio-temporal objects is established,the typical cause-effect consistency operation rules such as ordering rules,substitution rules and operation combination rules are improved,the mathematical description and evolution algorithm of the cause-effect consistency of multi-grain spatio-temporal objects are proposed,and the dynamic construction of the operation graph is realized.(3)A multi-granularity spatio-temporal object causal consistency detection and rule constraint method based on graph model is proposed.The type structure of operation graphs under different rule conditions is analyzed,and three types of consistency conflicts,such as result inconsistency,divergence conflict and deadlock conflict,are summarized for multi-granularity spatio-temporal object operation graphs;based on the operation rule set,a terminability and convergence detection method for object operation flow is proposed;for two types of causal consistency conflicts,such as deadlock and divergence conflict dissipation and inconsistency conflict dissipation,an embedded rule constraint The proposed method is based on a set of operational rules.In this paper,a graph model representation of multi-grained spatio-temporal objects in the study region is realized with land use classification co-editing as an example.Based on the land use editing operation rules,the causal consistency problem in the co-editing operation flow in the region is explored,and the feasibility of the causal consistency detection and constraint methods is verified.The research in this paper can provide some reference for the study of the causal consistency of the collaborative operation flow of multi-grained spatio-temporal objects.