A valve for controlling fluids having an actuator unit for actuating a valve member, which has a first piston and a second piston, separated from it by a hydraulic chamber, and which actuates a valve closing member that divides a low-pressure region at system pressure from a high-pressure region. The combustion product sulfur dioxide is fed to a gas chromatograph in which it is separated from other combustion products and is then fed to a detector, which is situated downstream and which is provided for determining sulfur dioxide concentration. The cartridge electrode further includes a second contact portion provided for being electrically connected to a process means of the cartridge, and an injection receiving portion into which resin is injected when the cartridge electrode is molded into the frame. The first three-dimensional view and the second three-dimensional view are rendered in real-time. A system that can transport upstream RF signals generated by devices such as a set top box or a cable modem, through a passive Optical Network while simultaneously supporting downstream RF video and bi-directional base-band services on the PON.