Wireless Sensor and Actuator Networks for Lighting Energy ...

deliberately perturbed the lights during the test to encourage more frequent use of the
overriding mechanisms for pertinent comments from the participants. The test
procedure for the subjects who started with the research system is listed as follows and
that for participants who started with the commercial system is very similar and can be
found in Appendix B.2.
(1) Participants start with the initial desktop illuminance of 500 lux under the
research system, use the GUI controller to set the lighting to a comfortable level,
and begin to work on the task of their choice.
(2) At the 5 th , 10 th and 15 th minutes, the lights are dimmed or brightened by the
investigator. This is to encourage the participants to override to return the lights
to a comfortable level.
(3) At the 20 th minute the investigator stops the first session of the experiment and
asks the participants to take a 10-minute break outside the office. Meanwhile, the
investigator resumes the data collection and documentation part of the sensor
placement experiment as described in the previous section. Before the
participants enter the office again for the second 20-minute experiment, the
investigator switches the lights to the commercial photosensor-dimming system
and sets the initial desktop illuminance to 500 lux. Participants are asked to use
the remote controller to override the initial lighting to a comfortable level after
settling for the remaining experiment.
(4) At the 5 th , 10 th and 15 th minutes of the second session, the lights are again
dimmed or brightened by the investigator using a second remote controller
without notifying the participants.
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