A device for generating an inhomogeneous electrical field includes first and second electrodes. at a strain rate of 1 radsec, and wherein the sulfopolyester comprising less than about 25 mole % of residues of at least one sulfomonomer, based on the total moles of diacid or diol residues. This structure allows the accelerator to compress the resin with pressure applied to the PWB, so that the resin tends to flow along the circuit board. The intermediate layer is arranged on the heat-radiation surface of the base plate, projects from the level of the projecting portion of the cover in a thickness direction, and is made of a thermoplastic material in a solid-phase state. The traffic data includes vehicle location information and network traffic congestion information. 0 Vm or less, which satisfies the TCO guideline, can be realized.