Failure mode and effects analysisFailure mode and effects analysis (FMEA; often written with "failure modes" in plural) is the process of reviewing as many components, assemblies, and subsystems as possible to identify potential failure modes in a system and their causes and effects. For each component, the failure modes and their resulting effects on the rest of the system are recorded in a specific FMEA worksheet. There are numerous variations of such worksheets.
Protection ringIn computer science, hierarchical protection domains, often called protection rings, are mechanisms to protect data and functionality from faults (by improving fault tolerance) and malicious behavior (by providing computer security). Computer operating systems provide different levels of access to resources. A protection ring is one of two or more hierarchical levels or layers of privilege within the architecture of a computer system. This is generally hardware-enforced by some CPU architectures that provide different CPU modes at the hardware or microcode level.
Pope John Paul IIPope John Paul II (Ioannes Paulus II; Giovanni Paolo II; Jan Paweł II; born Karol Józef Wojtyła 'karol-'józew-woj'tyła; 18 May 1920 - 2 April 2005) was head of the Catholic Church and sovereign of the Vatican City State from 1978 until his death in 2005. He was later canonised as Pope Saint John Paul II. In his youth, Wojtyła dabbled in stage acting. He graduated with excellent grades from an all-boys high school in Wadowice, Poland, shortly before the start of World War II in 1938.
Airborne early warning and controlAn airborne early warning and control (AEW&C) system is an airborne radar system designed to detect aircraft, ships, vehicles, missiles, and other incoming projectiles at long ranges and perform command and control of the battlespace in an air engagement by directing fighter and attack aircraft strikes. AEW&C units are also used to carry out surveillance, including over ground targets and frequently perform battle management command and control (BMC2).
Negation as failureNegation as failure (NAF, for short) is a non-monotonic inference rule in logic programming, used to derive (i.e. that is assumed not to hold) from failure to derive . Note that can be different from the statement of the logical negation of , depending on the completeness of the inference algorithm and thus also on the formal logic system. Negation as failure has been an important feature of logic programming since the earliest days of both Planner and Prolog. In Prolog, it is usually implemented using Prolog's extralogical constructs.
