Sensor - a transducer device which indicates physical status of a system or the environment in which it operates with an electrical signal to encode the system/environment characteristic it is designed to measure - e.g. a thermistor, a position encoder, limit switch, stress/strain gauge, pressure transducer, ...
Service - a specific computation provided based on inputs which produces a required output in order to meet a system requirement.
Service Release - when an external event sensed by an embedded system indicates a request for service, the thread which provides the service is released - e.g. an ISR can do a semaphore give to indicate sensor data is available for processing.
Set Associative Cache - A cache which allows main memory addresses to be loaded in N different cache lines - a set associative cache is said to be N ways, where each way is a different cache line which the same address data may be loaded - e.g. 32 way set associative cache.
SEU - Single Event Upset, a phenomina where a memory bit is flipped due to an environmental influence such as electromagnetic radiation. The bitís original value may be restored if the SEU can be detected and corrected by a system monitoring technique.