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Title
Mapping without the sun
Author
Zhang, Jixian

a result, the process no longer describes a global birth-and-death
but regional expansions and shrinkages of the sets under study
namely the front, the seats and the scar of the spread. We draw
from the model instructive simulations and a precise predictor of
scars that actually occurred in the State of Selangor during the
period 2000-2004.
For the moment, fire daily predictions were not tested. This will
be a future work to undertake.
Figure 8: Cumulative number of hot spots from 2000 to 2004,
during the periods April-June (a), July-September (b), and
October-December (c).
a) b) c)
ACKNOWLEDGEMENTS
The authors would like to thank The Cilix Corp. for having al
lowed them to use their maps of fuel combustion and spread rate.
REFERENCES
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Figure 9: a) cumulative number of hot spots from 2000 to 2004,
during the period January to March, b) and c) two simulations
based on the input set a) with two values of k in the ratio 1.5.
Selangor area a(S) is equal to 79, 969 pixels, and in the simula
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set S of Selangor is 500. On the other hand, the sum of the fuel
amount over S equals 304,130, in dimensionless units. There
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J s 0{x)d(x) = 7 g°g 6g = k f fw{x)d(x)
from which we draw
304,130
79,969 k
k = 1.64 x 10~ 3
(21)
4.2 Fire spread simulations
If Io stands for the input set, then each point x of Io is replaced
by one of the discs of Figure7, according to the value r(x) of the
spread rate map at point x, which results in 5(x). Then, the simu
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Figure 9b and c depict two propagation simulations <5(/i) when
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5 CONCLUSIONS AND FUTURE WORK
This paper proposes a new Random set model, the random spread.
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