Analysis Techniques For Man-Machine Systems Design

NATO UNCLASSTIFIE9 AC/243(Panel 8)TR/7Volume 22.2. FUNCTION ORIENTED VIEWA function oriented view can be applied for determining activities of a system, i.e., system functions and subfunctions.their hierarchical structure and their interactions.2.2.1. Function oriented hierarchical relationshipsThe application of hierarchical relationships results in a decomposition structure of systemfunctions, i.e., a hierarchy of subfunctions. The hierarchy can be represented as a list (2.2.1.1)or as a diagram (2.2.1.2).sFST2.2.1.1. Listing of function oriented hierarchical relationshipsExample: Hierarchical decomposition of functions of a ship engine control systemI. Control propulsion subsystems (PSS)A. Execute PSS requests of the bridge1. Execute diesel requestsa) Start diesel(1) Acknowledge start diesel request(2) Check start readiness(3) Activate start(4) Monitor start(5) Report start completion(6) Identify start unreadiness cause(7) Report start unreadiness(8)(9)Identify start failureReport start failureb) Stop dieselc) Change over to diesel2. Execute hydraulic clutch requestsa) Fill hydraulic clutchb) Empty hydraulic clutch3. Execute gas turbine requestsa) Start gas turbineb) Stop gas turbinec) Change over to gas turbine4. Execute speed change requests5. Execute mode change requestsB. Monitor PSS1. Monitor diesel and its auxilliary systems2. Monitor gas turbine and its auxilliary systems3. Monitor energy transfer systemsC. Handle PSS failures1. Handle failures of diesel and its auxilliary systems2. Handle failures of gas turbine and its auxilliary systems3. Handle failures of energy transfer systemsII. Manage energy supplym. Manage ship safetyNATO ITNCLASSIFIED