A wheel for a non-motorized vehicle can include a housing assembly and a tread assembly. When the operation lever is operated from the neutral path to a linking path, the second link mechanism establishes operative coupling between the operation lever and the parking brake mechanism. An improved method of simulating gaussian blur and an approximation equation that relates a known gaussian blur quantity to a known pillbox quantity are used in conjunction with a non-linear blur difference equation. When the indication of sensing of the data signal is formed, the switch is closed, and the power supply is connected to the homeplug device operative power is provided to power the homeplug device.