Abstract: With the development of wireless communication and positioning technology,the index techniques for indoor moving objects are more and more important in location-based services (LBSs).The structure of the indoor scenes structure is complex and diverse,while previous studies regard rooms,corridors,stairways and other indoor entities as the same cells and model a moving object by a moving point,which do not distinguish different semantic meanings between them and do not consider access issues between the objects and cells.To solve this problem,this paper studied a new method of indoor index technique based on semantics and presented an efficient trajectory query processing algorithm based on semantics and access permission.In addition,this paper also proposed an indoor semantic-based model,which gives the formal description of semantics and accesses permission of indoor cells and moving objects.Extensive experiments demonstrate that the proposed index structure is effective,robust and more efficient than the ACII and RTR-tree in several aspects.

Key words: Moving objects,Indoor scene,Index,Semantics,Trajectory queries