There is provided a system for facilitating a conference call. Many typical stimulation devices suffer from deficiencies in providing complex stimulation patterns. The poor visibility of detailed features in the dark area may reduce the detection rate of anomaly. The tail portion of the lock pin may be manually retracted by an operator while the phaser is being installed or removed from the engine, thus preventing damage from high torque exerted via the phaser attachment bolt in bolting the phaser to the engine. These temperature changes can be relayed to alert an operator of the change in physical andor chemical properties within the system so that remedial action can be taken. A control center, an ultraviolet fluid treatment apparatus, and a method of treating a fluid are also disclosed.