A cold-cathode fluorescent lamp including a glass bulb and a pair of electrodes which are cylindrical and respectively inserted in two ends of the glass bulb. The optical loss may be introduced with an anti-phased ohmic contacts. A processor and a sensor system monitor parameters such as torque, speed, magnetic flux, etc. Drive for the compressors is provided by an electric motor, preferably a permanent magnet motor, disposed between the first and second compressor casings and comprising a stator and a rotor rotatable within the stator. A summary instance of the summary is created for each sample.