Schema of Uncertain Spatiotemporal XML Data

1 Introduction

At present, with the development of temporal database and spatial database, scholars have further created spatiotemporal database which is more conducive to spatiotemporal data management(Ye et al., 2007). Compared with the traditional relational database, the biggest advantage of spatiotemporal database is that it supports spatiotemporal data effectively and avoids a large amount of data redundancy caused by the change of the relationship between temporal and spatial attributes in the traditional relational database. Much research has been done to address the modeling and manipulation of spatiotemporal data (Pelekis et al. 2004; Wang et al. 2000; Yuan et al. 2010). (Wang et al., 2000) proposed two spatiotemporal data models: abstract model and conceptual model. In the comprehensive research of spatiotemporal data modeling (Pelekis et al., 2004), many existing spatiotemporal data models are summarized and compared, such as snapshot model, spatiotemporal composite data model, data model based on simple timestamp and so on. In the aspect of spatiotemporal data modeling, Chen et al.(Chen et al 2016) proposed a spatiotemporal data model based on compressed linear reference. (Cheng et al., 2021) proposed a dynamic spatiotemporal logic to represent and reason dynamic spatiotemporal knowledge. Because of the fuzziness and uncertainty of information in the real world, Bai et al.(Bai et al., 2015) put forward the research of fuzzy spatiotemporal XML data Schema.

The temporal data model based on XML can process the temporal data well and manage the temporal data effectively(Ye et al., 2007). In the literature (Ye et al., 2007; Zhang et al., 2009; Rizzolo et al., 2008), the research results of XML-based temporal data model by domestic and foreign researchers in recent years are fully displayed. Reference (Chen et al., 2006) focuses on the research of temporal XML indexing. All the above studies take advantage of XML's convenience in expressing tenses. However, objects in the real world have spatial attributes as well as temporal attributes, so the study of spatiotemporal data becomes an indispensable part. Spatiotemporal database, as an important research direction of emerging database, has more important and extensive application fields and practical significance, which has aroused strong concern of scholars at home and abroad. Temporal database and spatial database are mature in their respective fields. On this basis, it is more natural for the fusion of the two to form a spatiotemporal data field. Nowadays, the research on spatiotemporal data at home and abroad is still in the primary stage, and the development is not mature enough, and there are still a lot of contents waiting for scholars to study in depth. The research of spatiotemporal data mainly focuses on the related aspects of data model, query and index, which can be reflected in references(Liu et al., 2013; Yu et al., 2012; Cao, 2011; Chen et al., 2009; Bai, 2010). At the same time, the unavoidable uncertainty of spatiotemporal data caused by data distortion, network delay or uncertainty of spatiotemporal data in the real world is also one of the research directions, such as literature(Gao, 2015; Bao, 2006). Literature (Guo et al., 2011; Ma et al., 2006; Hao et al., 2006) is about XML Schema specification research literature, related to XML Schema specification document design, indexing research direction.