A Raster Expression Of Spatial Orientation Relations For A Point Object

With the development of computers and spatial big data,the need for natural spatial reasoning has increased,and it is a great challenge to establish a practical mapping between spatial reasoning and human cognition.Because of the ambiguity and flexibility of natural language,there is also uncertainty about the expression of spatial orientation.Most of the current research on spatial orientation is for the absolute spatial relationship,the study of relative spatial orientation is relatively small,at the same time,most of the scholars are given a qualitative model description of the relative spatial orientation,and lack the qualitative and quantitative combined description.To solve the above problems,this paper proposes a relative orientation model for point objects and the corresponding spatial expression and inference rules on the basis of cone model and projection model,and expresses the spatial orientation relation based on this model in a grid form.The main research contents are as follows:1.The collection of spatial orientation words,through the processes of recording,screening,integration between the corpus and the modern Chinese dictionary as well as the orientation words appearing in other materials,is summarized into nine kinds of representative spatial orientation words,which include eight basic relative spatial orientations " before,after,left,right,left before,right before,right after,right after " and one kind of Pan orientation orientation word " around ".2.To determine the spatial orientation relationship model according to the word relative spatial orientation,summarize various qualitative expression methods such as quantitative expression of spatial orientation,cone model,projection model,and cross filament model,analyze and compare the advantages and disadvantages of each relative orientation expression model,based on which a cone projection model for a point object is proposed and validated by cognitive experiments.3.Multiple spatial orientation expression and inference rules were defined based on the property of spatial orientation,the spatial orientation was divided into median orientation relationship,positive orientation relationship and angular orientation relationship,and the inference combination results when different orientations were compounded were discussed and shown in the form of the spatial orientation combination table.4.Presented the raster data based expression and inference for point objects,rasterized point objects and spatial models,property's value based on raster data and spatial orientation combination table to complete the expression and preliminary inference of spatial orientation,for inference results not unique orientation combination relationship,according to the model determine its spatial orientation relationship in accordance with the given data.Integrating the above,this paper proposes the relative spatial orientation model and expression facing point object;completes the inference between the orientation relationships and the determination of the only orientation.The results show that the relative orientation judgment method based on raster data is beneficial for achieving the determination and inference of spatial orientation quickly,and it is helpful for the expression and indexing of spatial objects.A conversion bridge from natural language to GIS language can be constructed,which will help to establish efficient and intelligent geographic information services.