A switching power supply has a switching device connected via a primary winding of a transformer to DC input voltage; a circuit for rectifying voltage at a secondary winding of the transformer, and outputting an output signal; and a control circuit for controlling onoff states of the switching device. The optical fiber array is fixed within the V-shaped grooves of the glass substrate using a fixing adhesive. Controlled volumes of oxygen are admitted with the oxygen feed line into the combustion reactor depending on the sample for the complete combustion thereof. This eliminates the risk of contamination to electrical components and eliminates the need to apply additional lube during the products life. The phase and amplitude modulations after removal of NDM may be used for inversion, e. A spill basin is accommodated in the hollow space of the reservoir tank.