Methods, systems and computer program products for data fetching in a networked computing environment. The inverter bridge is controlled so that the curve of filtered average current in the DC intermediate circuit follows essentially the curve of the rectified AC supply voltage, the rectifier bridge is connected to the inverter bridge directly without a DC capacitor unit acting as an intermediate energy storage, and the curve of the power fed to the load has essentially the form sin2. In addition, prior to step b) or after step c) a reactive adhesive is introduced in such a way between the first and the second component that it bonds the first component to the peripheral zone of the second component, the reactive adhesive being cured or allowed to cure. The cassette includes a cassette body and a fluid pathway network for coupling the fluid drive system of the console with the probe. The method and apparatus are capable of enhancing efficiency and quality of verification by representing a plurality of images corresponding to changes of processing conditions at a time and comparing a plurality of the thus represented images with each other by an operator. The cathode includes a catalyst having characteristics of a pseudo capacitor and a binder, and an electrochemical apparatus for water purification including the same.