ISPRS, Vol.34, Part 2W2, “Dynamic and Multi-Dimensional GIS", Bangkok, May 23-25, 2001 
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4. Dynamic Management Spatial-Temporal 
Information System "DyMSIS" 
DyMSIS was created by converting the DiMSIS data structure 
proposed in [1] to KIWI+ format, and can be considered the 
successor system to DiMSIS. DyMSIS has the constitution 
shown in Figure 3. 1 2 3 4 5 
Application Subsystei 
A 
^ Core Subsystem ^ 
f 
AS 
Attribute 
Database 
V 
Geographic Data 
(KIWI+ format) 
V 
Initializing 
Information 
Vectors Connectors 
Figure 3. System Constitution 
(1) Geographic data comprised of vectors and connectors 
(KIWI+ format) 
(2) Core subsystem that executes management, plotting, and 
search of geographic data 
(3) Initializing information including feature space definitions 
(4) Application subsystem that constructs a GUI and refers to 
and renews the attribute database 
(5) Attribute database related to connector information 
5. Spatial Temporal Analysis 
5.1. Concept 
By means of spatial temporal data management, analysis using 
temporal factors (spatial temporal analysis) becomes possible. 
When such analysis is performed, the comparison of information 
between two specified time points becomes an essential function. 
It is possible to observe changes in feature space regions 
(points, lines, areas, volumes) between two time points by 
overlaying map data for the two time points (Figure 4). However, 
in general, in order to track changes in all map data for the two 
points, a considerable amount of time is required for this 
operation. In order to reduce the time required, we propose the 
method of calculating data corresponding to the overlay results 
prior to data input. With this method, as for comparison between 
two time points, if the types of data overlaid are the same and 
known, the method is considered effective. 
Figure 4. Overlay of data for two time points 
5.2. Algorithm for calculating differentials between two time 
points 
Inputs and outputs of the algorithm for calculating changes in 
area between two time points are as follows (Figure 5). 
Inputs: 
[Positional information] 
Representative point P identifying the target region of feature 
space. 
[Feature space information] 
Feature space D defining the target region of feature space. 
[Temporal information] 
Time point (T) used as reference for comparison of temporal 
information (T,T). 
Outputs: 
(1) Representative point Q (one point) identifying region of 
feature space at time point used as comparison reference. 
(2) Representative points Q'1 - Q'N (N points) identifying region 
of feature space at time point used as comparison target, 
and feature space region comparisons R'1 - R'N between a 
feature space region and parts of feature space contained in 
a comparison reference region within that region.