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Temporal processes

A temporal process is similar to a QPT process. It selects regions from individual or composite fields and imposes direct influences on their values. A temporal process is represented as a field and acts on each individual point in the selected regions. Since a region is not a fixed object, but can be decomposed with respect to other fields, parts of the region may be influenced by other processes. The process fields are composed in order to determine the net change to the values in the influenced fields and to update the region structures.

We describe temporal processes with a syntax similar to QPT's but adapted to our model as follows:

The following example models the warming of each atomic region in the composite field of irradiation, shade and temperature. The heating-rate is inversely proportional to the amount of shade. The process stops when the irradiation is reduced to zero.


temporal-process solar-warming

:regions (r :fields (irradiation shade temp)

:atomic T

:conditions (> (irradiation r) zero)

:variables heating-rate

:relations (qprop- heating-rate (shade r))

:influences (I+ (temp r) heating-rate)

:stop-conditions (<= (irradiation r) zero)


next up previous
Next: Spatial processes Up: Dynamic model: behaviour Previous: Dynamic model: behaviour

Monika Lundell
Tue Mar 11 14:28:30 MET 1997