An electrophotographic image forming apparatus to which a process cartridge is detachably mountable, the process cartridge can be positioned with high accuracy in a simple construction in an apparatus main body. The decoder includes a memory and a processor coupled to the memory. Fluids can be inserted into an open microfluidic channel by using open sections of the open microfluidic network. The power uptake and the current output are adapted without losses and the alternating current generated by the generator is transferred to an averaging direct-current circuit.