Global Positioning Systems are proliferating the fleet industry. If you´ve thought about how these systems affect your privacy, consider this: A man has been charged with violating California´s stalking laws after he allegedly used a Global Positioning System device to track and stalk his ex-girlfriend, according to an Associated Press report and a story in Land Line Magazine.Ara Gabrielyan, 32, of Glendale, Calif., was arrested August 29 on one count of stalking and three counts of making criminal threats. Police said Gabrielyan attached a cellular phone to the woman´s car with a motion switch that turned on when the car moved, transmitting a signal each minute to a satellite. Information was then sent to a Web site that allowed Gabrielyan to monitor the woman´s location, the AP said.The woman learned how Gabrielyan was following her when she discovered him under her car attempting to change the cell phone´s battery, police said.Police allege Gabrielyan threatened over a six-month period to kill himself and the woman. He could face up to six years in prison if convicted.Some proposals for placing GPS devices in trucks for tracking loads, especially hazardous materials has generated considerable opposition in the industry, according to Land Line.