A distributed cache management system that minimizes invalid cache notification events is provided. The image processor determines roadway width by identifying roadway marker signs and oncoming traffic in processed images captured by the image sensor and determining the number of lanes, vehicle location on the roadway based on the roadway size andor width and location of oncoming traffic. Coatings prepared from the coating composition may be employed to provide corrosion resistance to metal substrates. The switch control circuit drives the switching device in light load mode when a flyback voltage developed by the transformer terminates earlier than each clock pulse, and in heavy load mode, in which each on-off cycle of the switching device is longer than in the light load mode, when the flyback voltage terminates later than each clock pulse. Calibration systems are also disclosed. The wiring portion has two carrying portions at opposite sides, respectively.