Environmental Engineering Reference
In-Depth Information
100
100
Calibration (out)
Calibration (in)
RBF
80
ISD
50
case 4
case 1
case 2
case 3
60
0
40
RBF side 1
RBF side 2
ISD side 2
CAL side 2
−
50
ISD side 1
20
CAL side 1
−
100
0
0
50
100 150
inflow direction (degrees)
200
250
300
0
50
100 150
wind direction (degrees)
200
250
300
Fig. 2.
Lowest-layer angular response (a) and vertical profiles of the angular response (b) of the
RBF and ISD metamodels
4. Conclusions
A two-way coupled mesoscale-microscale model system was implemented using
two alternative formulations of interpolating metamodels for simulating the effect
of local forcings on the mesoscale field. The system was evaluated in calculations
of the flow fields in the urban area of Athens, Greece. The performance of two
metamodelling formulations was evaluated by observing their response to input
conditions extracted from microscale simulations of a densely-built downtown
location. The performance of the RBF neural network metamodel was found to be
superior to that of the ISD interpolator both in terms of accuracy and predictive
ability.
References
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, 629-644 (2006)
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