Complex sentence: Shipboard Global Maritime Distress Safety System (GMDSS) installations include one or more Search and Rescue Transponder (SART) devices which are used to locate a survival craft or distressed vessel by creating a series of dots on a rescuing ship's radar display.
Split into simpler sentences: Shipboard Global Maritime Distress Safety System (GMDSS) installations include one or more search and rescue locating devices. The radar-SART is used to locate a survival craft or distressed vessel by creating a series of dots on a rescuing ship's radar display.