In lieu of a human operator, the machine is activated using a specially programmed Arduino microcontroller.

BBC: Zipwhip's Textpresso

At this point a human operator decides whether the unusual behaviour detected is permissible.

ECONOMIST: A thousand ills require a thousand cures

With the aid of some mathematical finagling this picture can be reduced to a mere three dimensions, for display to a human operator.

ECONOMIST: Wine-tasting will never be the same again

Once the computer has learnt what's what, it can recognise and compare smells, or can give its human operator the chance to do so.

ECONOMIST: Wine-tasting will never be the same again

Some experts have commented that Angel Ambush was not 'real' augmented reality at all, because the virtual angel was just a layer of video manipulated by a human operator, rather than an independent 3D object.

BBC: Augmented reality goes beyond gimmicks for business

Though a program displays panels showing all the critical processes of a real rig (fire and gas detectors, valve status, oil flow from the sea bed and so on), and then responds to the actions of the trainee by altering these displays appropriately, a human operator can intervene at any time if things seem to be going too smoothly.

ECONOMIST: Virtual reality

Now, Workday is a full-blown enterprise resource planning (ERP) operator, providing must-have functions like human resources, payroll and financials.

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