A wave-powered water vehicle includes a surface float, a submerged swimmer, and a tether which connects the float and the swimmer, so that the swimmer moves up and down as a result of wave motion. The method comprises steps of forming a first oxide layer over the substrate and forming a nitride layer on the first oxide layer. The instruction input unit separately encrypts each description about process details for the servers using a public key for the corresponding server, creates instruction forms containing the encrypted descriptions, and sends the instruction forms to the server providing the page dividing service. The gas stream cleaned of alkali chlorides is directed to a reaction area where particulate material containing mercury contaminants is inserted into the gas stream to vaporize the contaminants from the material and entrain the cleaned material in the gases. When the end of the pin is in a second end of the guide groove of the switch member, the other end of the pin is in an unlocking position disengaged from the positioning notch of the locking plate, thereby allowing independent rotations of the crank and the wheel frame.