There are a number of different electronic training aids, including an anti-bark collar, remote control collars used to control any unwanted behaviour, electric shock training leads and electric boundary or "freedom" fences.

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Traditional blue-collar labor is often associated with rational control, along with modern high-reliability organizations, such as military, public safety, nuclear energy production, and oil platform operations.

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At one point, the BLS listed some 200 jobs as blue collar that ran the gamut from auto mechanics to crane operators, from garbage collection to pest control.

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