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temporal knowledge representation based on the explicit
description of possible changes to geographic phenomena
modeled at a high level of abstraction as identifiable objects.
Starting with a set of basic types of change with respect to the
existence and non-existence of objects with identity, a
methodology was presented that systematically built on these
fundamental concepts and derived further types of change that
were possible. This change-based model provided a better
understanding of the set of possible alterations to which an
object can be subject as it evolved over space and time and
enabled the extension of spatial data models and the
development of GIS query languages that incorporate such
semantics of change. Although no explicitly spatial information
has been incorporated in this model of change, it has been
shown that tracking changes to an object’s identity over periods
of existence and nonexistence, gives useful insights into the
behavior of an object over time that are relevant to many cases
of spatio-temporal change. Christophe Claramunt proposed a
standard way of designing STPs, aimed valid for every data
model that supports the time and space dimensions. He
presented a taxonomy of basic STPs, extended the spatio-
temporal processed in two ways, and derived a complete
classification, including endogenous approach and exogenous
processes, consisted of Translation, Succession and Permutation,
Re-allocation, Split and Union, Production, Reproduction and
Transmission, introduced related database modeling issues,
expressed three design patterns in a spatio-temporal object-
relationship data mode (Christophe Claramunt 1997).
2.2 Spatio-temporal Process Classification
In this paper, we propose a practical classification of Spatio-
temporal process. For the reason of actually implementation, we
get used to the conception of Layers, Such as we know, Layers
are widely used for the construction of geographical data, when
we construct the spatio-temporal data storage in the database,
there are three features patterns, includes points, lines and
polygons within a layer, for each geographical object or
phenomenon, it is able to represent in the three patterns of
features. On the basis of three patterns, classification
corresponding each pattern is proposed to describe the process
of change of spatio-temporal objects. Hence we draw up a
spatio-temporal process taxonomy which is used for the
taxonomy of STP by the analyzing of essence of phenomena
change, it can be showed in the following graph:
Figure 1. A graph for taxonomy of STP
The procedure that from start to end has no difference except
the time variable has been changed, we name it a REMAIN
process, this process is easily ignored, but in the real database,
the record about this information is solidly stored in the Spatial-
temporal database.
Apart from the process of REMAIN, we propose a detail
definition of the spatio-temporal change patterns,
transformation occurred during the Spatial-temporal process
could be reflected in many ways, in the paper, we plan to
classified them in two aspects, one of them occurred in the
geometric aspect, we give it a name GEOMETRIC CHANGE;
Another can be happened in thematic way, which can be named
after THEMATIC CHANGE, the reason for this classification
lies in a logical design pattern of database, there is a common
way for the data storing strategy that the geometric data and
property data are separately deposited but with a weak relation
by the using of keywords.
Refer to the GEOMETRIC CHANGE, we propose a deep
classification which are named INDEPENDENT CHANGE and
DEPENDENT CHANGE, the rules for this division base on
whether the process of one spatio-temporal object is depend on
that of another or not, there are two kinds change for this
division, the first one which the procedure of change without
identity verified is a endogenous process, the second one,
exogenous process, companioned by transformation of objects
identities change in most time. We assume exogenous process is
prior to independent change, because only one object has been
bom(or created), some process could take place in the
independent change. Those two kinds of conceptual process
need to be classified in an embodying way.
2.2.1 Embodiment of DEPENDENT CHANGE
The first process of DEPENDENT CHANGE is BORE, for
each spatio-temporal object, the creation is the most and the
very beginning step during it’s life circle, the BORE process, is
a opposite process of DIE, means that a newly objects exist
after a death of others, also has many instances.
The Second process we name it DIE, the process is regarded as
a termination of a spatio-temporal objects, The DIE process can
be described in such a way, the identity of the object has change
into another or the geometry has vanished, the process is a
creation of the new objects, leading to the contrary process of
BORE.
We propose SPLIT as a basic process for the description of
change occurred involving several spatio-temporal objects, for
the SPLIT process, at the beginning, there is one object has an
integral part of geometric properties, in the end, newly bom
objects have been created, with the initiate state would be
The last process we propose for the concreting of geometric
change, in the UNITE process, several object will be united into
one objects, companioned by the reducing of identities for the
objects and the geometrical transformation, as a result, the
former objects were replaced by one objects. The process often
have a expanding of area.
2.2.2 Embodiment of INDEPENDENT CHANGE
There is a common phenomenon that a spatio-temporal object
enlarge it’s size due to a lot of reasons, in order to represent this
kind of process, we name EXPAND, by the demonstrating of
growing space the object occupied, this phenomenon can be a
basic classification of spatio-temporal process, which may be
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