Ideally,homeowners want to be warned if a burglar sneaks onto their property, and farmers want to know if horses or sheep are no longer in the paddock or field they were left grazing in. Experimental physicists at Saarland University absorb developed a flexible security solution that can be used in gardens, and driveways,trade premises, or on grazing land and in woodland. The sensor cable system that Professor Uwe Hartmann and his team absorb developed issues a warning sign indicating if and where someone has attempted to cross over the cable. The cable itself can be fixed to long stretches of fencing, and hung in trees or even buried underground. It monitors the Earth's magnetic field and reliably issues a warning message to,say, a smartphone whenever it registers a change in the field strength.
Source: phys.org