174
Process:
2. Monitoring and execution of the voyage
Name
Date
Created:
Mathes
9.3.98
Data flow:
Ship data
Checked:
1. Origin
• The origin of the ship data used must be known and verifiable.
• Safety-critical ship data must originate from an “authorised source”.
2. Validity
• The correctness of ship data used in the system must be verified.
• Changes in ship data necessitate a renewed check on validity.
3. Quality
• The accuracy of the ship data used must be selected in accordance with the tasks of integrated
navigation. In principle, no accuracy levels higher than those obtainable with the particular
measuring methods used must be quoted.
• Ship data used must describe the actual current state of the ship. The time of data input must be
comprehensible. Variables which are subject to fairly frequent modification (e.g. draughts, overall
height) should be the subject of particular attention here.
• Ship data used must be checked for consistency. This applies particularly if the same variable is
stored several times, e.g. in differing components. The desired aim is to have a jointly used uni
form data base for ship data.
• The input of redundant data (e.g. “incremental dimensions" in the case of ship dimensions)
should be avoided. If redundancies occur, they should be checked for freedom from
contradiction.
4. Harmonisation
• When inputting and processing ship data, care should be taken to ensure a uniform reference
system. This applies for example to units used for dimensions (preferably in [m])
or speeds (knots).
5. Criticality
• Modification of ship data may only be undertaken by authorised personnel. Access must be
restricted for example by the use of passwords.
6. Limit values and alarm facilities
• Lapses of consistency or plausibility must trigger corresponding warnings on input.
• Inconsistencies - particularly when using several data bases - must be detected by the
system; appropriate warnings should be issued.
7. Representation/display
• Ship data used in the system must be displayed in suitable form.
