light characteristic
Let an agent explain light characteristics and their notation, relay the standard classes and abbreviations from hydrographic sources, describe how mariners use them, and distinguish light characteristics from daymarks, sound signals and electronic aids.
Bundle → Layer → Finding → Questions Filled
4 bundles · 8 layers · 8 findings · 16 questions
Understand What a light characteristic is.
Definition
Definition.
Definition
Definition.
- What is a light characteristic, and how does it differ from daymarks, sound signals and electronic aids? definition
- Is the question about characteristics in general, a class or a specific light? boundary
Classes
Classes.
Classes
Classes.
- How do fixed, flashing, long flashing, group flashing, occulting, group occulting, isophase and quick lights differ? definition
- Which entry fits the specific class? action
Use Use at sea.
Reading
Reading charts and lists.
Reading
Reading.
- How are characteristics abbreviated on charts and in light lists, and how are they timed at sea? action
- Which references are standard? provenance
Identification
Identifying lights.
Identification
Identification.
- How do mariners identify lights by rhythm, colour, sector and range? action
- Which sources are cited? provenance
Standards Standards.
IALA
IALA and IHO.
IALA
IALA.
- What do IALA and IHO standards specify for light characteristics and chart symbols? provenance
- Which entry fits IALA? action
Technology
Technology.
Technology
Technology.
- How do lamps, LEDs and flashers produce characteristics? provenance
- Which entry fits lighthouse optics? action
Context History.
History
History.
History
History.
- How did light characteristics develop from fixed fires to rotating optics and standardised rhythms? provenance
- Which entry fits the history of lighthouses? action
Related
Related aids.
Related
Related.
- How do sector lights, leading lights and buoyage systems complement characteristics? provenance
- Which entry fits IALA maritime buoyage system? action
Classifiers Filled
- Family
- Thing Registry
- Category
- Cross-cutting context
- Entry kind
- thing
- Plane
- XCT
- Domain
- XCT.QLT
- Other names and narrower kinds
- fixed light, flashing light, long flashing light, group long flashing light, occulting light, group occulting light, isophase light, quick light, interrupted quick light, very quick light, interrupted very quick light, group quick light
What it is Filled
The pattern of light shown by a lighthouse, buoy or beacon that identifies it to mariners at night, described by rhythm, colour and period, in classes such as fixed lights that shine steadily, flashing lights where the light is shorter than the dark, long flashing lights with flashes of two seconds or more, group flashing and group long flashing lights with flashes in groups, occulting and group occulting lights where the dark is shorter than the light, isophase lights with equal periods, and quick and very quick lights; characteristics are recorded in light lists and on charts.
Why it exists Filled
Let an agent explain light characteristics and their notation, relay the standard classes and abbreviations from hydrographic sources, describe how mariners use them, and distinguish light characteristics from daymarks, sound signals and electronic aids.
Distinguishing features Filled
- Rhythm classes
- Colour and period
- Standard abbreviations
- Charted
What robots and AI may and may not do Filled
Must not
- Present outdated light list data as current.
- Confuse flashing and occulting lights.
- Tell a mariner to navigate by a light characteristic without checking the official chart.
- Report a light as working without evidence when it may have failed.
Only with a human decision
- Reporting a failed or wrong light to the lighthouse authority.
May
- Explain the classes of light characteristic and how they are written on charts.
- Report a light's characteristic from the current official light list, with its date.
Moral aspects Filled
- Mariners' lives depend on reading lights correctly.
- Lighthouses are also heritage for coastal communities.
Who is affected
- Mariners
- Fishers
- Coastal communities
Owners Filled
Steward
The national lighthouse authority that operates the light.
Master systems
- Official lists of lights and nautical charts
Links to other meta-models Filled
parent
- Q937228 - registry parent class
related
- property - in registry terms
- lighthouse - and buoys
- International Association of Marine Aids to Navigation and Lighthouse Authorities - IALA
- nautical chart - and light lists
What else AI and robots need to interact with it Filled
Identity and identifiers required Filled
- Vercy registry: vr.tr.light-characteristic
- Wikidata: Q1738955 (https://www.wikidata.org/wiki/Q1738955)
Direct properties not applicable Not applicable
- long flash minimum: 2 seconds
- quick light rate: 50-79 flashes per minute
- chart notation example: Fl(2) 10s note - two flashes every ten seconds
- standard body: IALA name
Plane XCT: no invented physical properties.
Recognition optional Filled
- Rhythm and colour pattern of a navigational light
- Fixed, flashing, long flashing, group flashing, group long flashing, occulting, group occulting, isophase, quick lights
- Daymarks are visual shapes; sound signals are fog horns; AIS and radar beacons are electronic
- Not a visible object as a concept; a rhythm of light at night.
Capabilities and actions required Filled
- explain classes and notation
- relay standards
- describe use in navigation
- distinguish related aids
Hazards and failure modes required Filled
- Misreading characteristics leading to navigational error
- Confusing flashing and occulting lights
- Stale light list data
Standards and interfaces required Filled
- IALA recommendations on light characteristics
- National light lists and chart symbol standards such as INT 1
- IHO chart specifications
Context of use required Filled
- Identifying navigational lights.
- fixed lights
- flashing and group flashing lights
- long flashing and group long flashing lights
- occulting and group occulting lights
- isophase lights
- quick, very quick and ultra quick lights
- composite and alternating lights
Sources Filled
- Wikidata item Q1738955: light characteristic - identity and sense of the item
- Wikipedia: Light characteristic - general description of the item
Open questions
- Should each characteristic class be a separate entry?
- How should hydrographic standards be linked?
- The registry entry has merged aliases naming classes; should they be split off?
Machine files
Provenance
thing registry research (pass 2) · unreviewed
Built from: models/things/publications/thing-q1738955/spec.json