A Class AB voltage-to-current converter includes a plurality of DC coupled transconductance stages that produce a linearized output and a biasing circuit. The client software executing on the client host composes a query and sends a data search request to the storage device. The present inventive system provides for, inter alia, automatic implementation of the present inventive method. A bandwidth limiter may be provided to balance the load through the router. Therefore, the partially complete image volumes can be acquired more quickly than the substantially complete image volumes to allow the scanhead to be scanned at a relatively fast speed. The hydrogen separator hardly generates defects such as cracks, peeling and the like in the hydrogen-separating layer, is superior in durability, and provides both good hydrogen-separating ability and good hydrogen permeability.