ISPRS, Vol.34, Part 2W2, “Dynamic and Multi-Dimensional GIS’’, Bangkok, May 23-25, 2001 
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A SPATIAL-TEMPORAL DATA MODEL FOR MOVING AREA PHENOMENA* 
Shanzhen Yl\ Yong ZHONG 1 , Lizhu ZHOU 1 , Jun CHEN 2 , Qilun LIU 1 
1 Department of computer technology and science 
Tsinghua University, 100084, Beijing, China 
Tel: 86-10-62789150 
E-mail: ysz@mail.tsinqhua.edu.cn 
dcszlz@mail.tsinghua edu.cn 
2 National Center of Geographic Information of China, Beijing, China 
Tel: 86-10-68424072 
Email:jchen@gps. ceic.gov.cn 
KEY WORDS: spatial-temporal data model, moving phenomena, GIS, database. 
ABSTRACT 
The spatial-temporal data model of moving object is a critical problem for spatial-temporal database, geographical information system, 
and multi-media information system. In this paper we give a spatial-temporal data model for moving area phenomena, named OPH 
model. In this model, the feature geometry of moving area object described by three sub-geometries, which are observation geometry 
of the moving area object, named O; currently present geometry of the moving area object, named P; and history geometry of the 
moving area object, named H. We give the definition of OPH, and than using the union, intersection, and difference of set theory to 
populate and update the value of OPH. We define the spatial-temporal topological relation between moving area object, then we give 
the spatial temporal operators and define trigger on OPH. 
*This research is supported by Natural Science Foundation of P.R.China (Number: 69833010). 
1. Introduction 
The researches of spatial-temporal data model include 
spatial geometry representation of variational spatial objects 
over time, spatial-temporal topological relation, and 
operation on them. In geographical information system 
(GIS), spatial phenomena (or object) usually be represented 
as vector graphics, such as point, line and polygon. The 
vector model can describe spatial distribution of spatial 
object, but could not represent evolvement for spatial object 
over time. The information of spatial distribution and 
temporal evolvement of spatial object is useful for many 
fields, such as moving point object of vehicle, ship, and 
aeroplane, moving area object of land use, weather, urban 
growth, and area pollution. Currently the observation of 
remote sensing provides huge different temporal location 
data of spatial object. In order to apply different spatial and 
temporal data to resolve the problem of interaction between 
spatial processes, to reply the spatial-temporal query, we 
need to research and develop spatial-temporal data model 
for spatial database. This paper contributes to the research 
of spatial-temporal data model of moving area object. 
There are many separate researches about spatial database 
and temporal database, these researches did not effectively 
combine spatial aspect and temporal aspect [Andrew Frank, 
1999. ]. The literatures for dynamic spatial object include 
David J.Wilcox 's Modeling Dynamic Polygon Objects 
[ David J.Wilcox, 2000 ] which models dynamic polygon 
object, gives Spatial Temporal Graph Model (STGM) and its 
data structure. In the graph the node represents polygon, 
direction edge represents relation of polygon evolvement. In 
temporal aspect, this model only represents the change of 
whole polygon, does not represent the growth, surviving, 
and disappearance of polygon object, can not reply 
spatial-temporal query. 
Donna J. Peuqeut gave an event-based spatio-temporal 
data model ( ESTDM) [ Donna J. Peuqeut 1995]. In this 
model the changed section of area object at an instant is 
regarded as an event, a series of changed sections of the 
object at different instants regarded as a list of events 
which recorded the changed value of object. The changed 
value is recorded by run-length-encoding. This model is 
based on raster model. 
Kathleen Hornsby and Max J, Egenhofer gave the concept 
of identity-based change [ Kathleen Hornsby 2000].They 
Introduced existence object, non-existing object without 
history and non-existing object with history, and brought 
forward continue existence object, new created object, 
recalled object, destroyed object, etc. but they do not give 
the data model and data structure. 
In this paper we consider area moving object (MO) in 
2-dimension plan Euclid space, discuss dynamic change 
and history of the object, and give spatial-temporal data 
representation, spatial-temporal topological relation, and 
several operators. 
2. The OPH model of area moving object 
Area objects in 2-dimension space are represented as 
geometry polygon or geometry function in spatial database. 
We usually use polygon representing spatial irregular area 
object, and use geometry function (such as rectangle, circle, 
etc.) representing regular area object. We name all of them 
as spatial geometry. 
We give the OPH model for area moving object. Where 
geometry O represents the observation geometry snapshot 
of area object at an instant, geometry P represents the 
sections of object which generated at past instant and 
continue existing at current instant, and geometry H 
represent the sections of object which existed during past 
period but did not existing at current instant. 
2.1 Spatial and temporal representation of area object