Wireless Sensor and Actuator Networks for Lighting Energy ...

mote sensors were arranged in a 3-by-2 matrix; each was programmed to acquire 10
illuminance readings every 5 seconds at the rate of 50 milliseconds per sample and to
send the data packet containing the readings along with the source mote ID to the base
station. To simplify the test, the sensors were configured into a single-hop centralized
network. In addition to the base mote, the base station consisted of a computer, which
ran a Matlab ® program with a Java I/O interfacing program to receive the incoming data
packets forwarded from the base mote, process the data, and carry out the mote-FVF
algorithm. The sensed illuminances transmitted in the mote network were digital values
from the ADC (analog-to-digital converters) on the mote. A separate calibration was
conducted in order to map the digital values to lux units.
4.4.2 Tuning the Parameters of the mote-FVF Algorithm
The parameters requiring tuning were a left and a right for the validation curve, the
fuzzification parameter m dif and the defuzzification parameter m mov for shifting the
center of the validation curve, the constant scaling factor , the fuzzification parameter
m e and the defuzzification parameter m for generating the adaptive parameter .
Without loss of generality, a left and a right were assigned to be the same to get a
symmetric validation curve as suggested by prior experiences and experiments.
Moreover, the values of a left and a right for each mote sensor were assigned identically, as
they were all of the same type and were expected to have similar characteristics. m dif
and m mov were adjusted so that the validation curve could shift enough to catch at least
some information of the possible largest change in a single time step without becoming
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