Wireless Sensor and Actuator Networks for Lighting Energy ...

Every subject was asked to participate in two consecutive sessions and worked under
both the research lighting system and the commercial lighting system.
In the first test, participants were permitted to place the wireless mote
photosensors at any location close to the desk, and the pertinence of the fused values
was compared to the readings recorded from a high fidelity light meter placed directly
at the center of subjects’ working area. Recommendations based on the results of this
test were made for future improvements and practical implementations.
The second test assessed user satisfaction with the overriding mechanisms
provided by both systems as well as the performances of the systems. The participants
were asked to set the lights to an ideal level with each of the overriding mechanisms
from the two systems. In the meantime, the fact that the lights were controlled by
different lighting systems in each consecutive session was concealed from the subjects,
and the participants were later asked for observations that distinguished the two tested
systems. The results have shown that the overriding system provided by the research
system was generally preferred, which implicated good design practice for lighting
overriding mechanisms. Furthermore, participants could not differentiate the
performance of the research system from that of the commercial system, which implied
that the research system could be superior to the commercial products when integrated
with intelligence.
The first test, the sensor placement test, was actually sandwiched between the
second test of comparing the research and commercial system to ensure the smoothness
of the test session and the best use of the participants’ time. In hopes of mitigating
possible bias, the order of each subject exposed to the research system and the
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