Abstract: The method of activating a vehicle fuel cell for ensuring maximum performance, improves performance of a polymer electrolyte membrane fuel cell, reduces a hydrogen usage, and has stable performance after manufactured. The method includes: placing a fuel cell in an activation device so as to be activated; changing a humidification state of a humidifier which supplies vapor to the fuel cell and a state of a cooling water; supplying a reactant gas to the fuel cell and maintaining a no-load state; maintaining a load state while changing a flow rate of the vapor and gas supplied to the fuel cell; changing the sate of the fuel cell to the no-load state, and re-supplying the reactant gas to the fuel cell; and comparing data measured when the fuel cell operates in the no-load state and data measured when the fuel cell operates in the load state respectively with a reference value.

Abstract: Disclosed is a circulating sewage/waste water purification device that improves purification efficiency of a first septic tank, improves maintenance and purification efficiency of a second septic tank, and simply exchanges a sewage purification material filled in the second septic tank with a new one. The circulating sewage/waste water purification device includes a first septic tank purifying sewage/waste water supplied from a sewage/waste water source, a second septic tank filled with a sewage purification material to purify the sewage/waste water purified by the first septic tank, and a third septic tank finally purifying the water purified by the second septic tank, the purified water, which has passed through the third septic tank, being again supplied to the sewage/waste water source.

Abstract: When operation of a fuel cell system has completed, residue in the fuel cell system such as water, fuel gas, and oxidant are removed by adsorbent stored in an adsorbent tank, which is connected to flow fields of the fuel cell system.