Sulfur dioxide (SO2) is irritating to eyes, skin and respiratory system. Volcanic Smog (vog) is produced from SO2 gas and is a hazard in Hawaii. Scientists monitor SO2 emission rates at KÄ«lauea volcano. Gas Plume during the 1984 eruption of Mauna Loa, Hawaii blocks out the sun.
Control Unit (CU) A control unit (CU) handles all processor control signals. It directs all input and output flow, fetches code for instructions from microprograms and directs other units and models by providing control and timing signals.
A power-train control module, abbreviated PCM, is an automotive component, a control unit, used on motor vehicles. It is generally a combined control unit, consisting of the engine control unit (ECU) and the transmission control unit (TCU). On some cars, such as many Chryslers, there are multiple computers: the PCM, the Transmission Control Unit, and the Body Control Module, for a total of three separate computers as an example. These automotive computers are generally very reliable. The PCM commonly controls more than 100 factors in a car or truck.