| http://www.w3.org/ns/prov#value | - a first infrared sensor having a pair of opposite polarity elements viewing closely adjacent zones such that, in response to a change in infrared radiation sensed, the output of one of the elements is a positive +A signal and the output of the other one of the elements is a negative -A signal; a second infrared sensor having at least one element viewing a zone substantially identical to one of
|
