IS:levelCrossing levelCrossings

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levelCrossing
 


Scheme description / Schemenbeschreibung

Position of levelCrossing in the XML-Tree / Position von levelCrossing im XML-Baum

Multiplicity / Anzahl

[0..∞]

Semantics / Bedeutung

A <levelCrossing> defines a crossing between a railway track and a non railway track (e.g. road, path).

Attributes of levelCrossing / Attribute von levelCrossing

  • id: XML-file-wide unique, machine-interpretable identity, required for later referencing that element internally. For a detailed explanation see Dev:identities.
    XML-Datei-weit eindeutige, maschineninterpretierbare Identität, die für die spätere interne Referenzierung dieses Elements erforderlich ist. Für eine detaillierte Erklärung siehe Dev:identities.
  • code (introduced with version 2.1): Machine-interpretable string (e.g. an abbreviation) used for identification of the object across exchange partners, usecase specific uniqueness constraints may apply. Please see our description of the differences between id, code and human-readable identifiers.
    Maschineninterpretierbare Zeichenkette (z.B. Abkürzung), die zur Identifizierung des Objekts auch bei Austauschpartnern verwendet wird, wobei spezifische Eindeutigkeitsbeschränkungen gelten können. Bitte beachten Sie unsere Erläuterung zu den Unterschieden zwischen id, code and menschenlesbaren Kennzeichnungen.
  • name: Established, human-readable short string, giving the object a name. Not intended for machine interpretation, please see our notice on human interpretable data fields.
    Etablierte, menschenlesbare kurze Zeichenkette, die das Objekt benennt. Nicht zur maschinellen Interpretation bestimmt, siehe Hinweise zu menschenlesbaren Datenfeldern.
  • description: Human-readable, more detailed description as addition to the name. It should give additional explanations or hints to the contents of this element. Not intended for machine interpretation, please see our notice on human interpretable data fields.
    Menschenlesbare, detailliertere Beschreibung als Ergänzung zu name. Sie soll zusätzliche Erläuterungen oder Hinweise auf den Inhalt dieses Elements geben. Nicht zur maschinellen Interpretation bestimmt, siehe Hinweise zu menschenlesbaren Datenfeldern.
  • xml:lang (introduced with version 2.1): This is a unique identifier of language. It uses basically the language standard IETF BCP 47 (external link) which may be different to ISO 639-1 (external link) or ISO 639-2 (external link). For mapping hints see relation to other standards (external link).
    This defines the language used for name and description. Use <additionalName> to provide a name and/or description in other languages.
🗒️ @pos describes the geometric centre of the <levelCrossing>. This approach differs from the one for bridges and tunnels, where @pos and @absPos describe by default the beginning of the element.


Das ist die Position des Elements auf einem Track i.S. der realen Entfernung zum trackBegin. Sie ist damit unabhängig von der mit absPos modellierten Strecken-Kilometrierung.

🗒️ For an explanation of the differences between @pos and @absPos see <mileageChange>
  • absPos: This is the position on a track as absolute mileage/chainage.
    Das ist die Position des Elements im Referenzsystem der Strecken-Kilometrierung.
🗒️ For an explanation of the differences between @pos and @absPos see <mileageChange>
  • absPosOffset (deprecated with version 2.1): The semantics of this attribute aren't very clear. It seems to be redundant to the definitions with mileageChanges in "overlapping regions".
  • dir: (deprecated with version 2.5) This defines the validity of <levelCrossing> along the track. Possible values are:
  • up: This denotes the direction from the <trackBegin> to the <trackEnd> (increasing relative position values).
  • down: This goes opposite to up (decreasing relative position values).
  • unknown: <levelCrossing> is restricted to a certain direction, but this direction is not known.
  • ocpStationRef: This refers to the id attribute of the associated <ocp> element.
    (introduced with version 2.1)
  • controllerRef: This refers to the id attribute of the associated <controller> element.
    (introduced with version 2.1)
  • length length of the level crossing from railway point of view. If @offset is not given, half of @length lies before @pos and halve after @pos.
  • angle crossing angle between road and railway in degrees
  • protection technical protection equipment at the level crossing
  • offset (introduced with version 2.5) describes how many meters of the @length value is before @pos. If @offset is not defined, by default @pos describes the geometric center of the level crossing (i.e. half of @length lies before @pos and halve after @pos).

Syntactic Constraints / Syntaktische Beschränkungen

  • id: xs:ID, required
    a string, starting with a letter (a..zA..Z) or an underscore (_),
    followed by a non-colonized and non-spaced string consisting of letters, digits, points (.), dashes (-) or underscores (_)
  • code: xs:string, optional
  • name: xs:string, optional
  • description: xs:string, optional
  • xml:lang: xs:language, language identification, optional
  • pos: tLengthM (xs:decimal, 6 fraction digits, length value measured in meter); required; must be greater than or equal to zero, less than or equal to the track's length
  • absPos: tLengthM (xs:decimal, 6 fraction digits, length value measured in meter); optional
  • absPosOffset: xs:decimal, 6 fraction digits, length value measured in meter; optional
  • dir: xs:string, generic type for more constrained direction statements: enumeration up, down, unknown; derived from tLaxDirection; optional
  • ocpStationRef xs:IDREF, optional
  • controllerRef xs:IDREF, optional
  • length: tLengthM (xs:decimal, 6 fraction digits, length value measured in meter); optional
🗒️ prior to railML® 2.4: length: tLengthM (xs:decimal, 6 fraction digits, length value measured in meter); default: 0,000; optional
  • angle: tAngleDegQuadrant (xs:decimal, 6 digits and 3 fraction digit with minimum value greater 0 and maximum less or equal 90, angle value measured in degree); optional
🗒️ prior to railML® 2.4: angle: tAngleDegQuadrant (xs:decimal, 6 digits and 3 fraction digit with minimum value greater 0 and maximum less or equal 90, angle value measured in degree); default: 90; optional
🗒️ prior to railML® 2.4: protection: xs:string; default: none; optional
  • offset: tLengthM (xs:decimal, 6 fraction digits, length value measured in meter); optional

Default values for length, angle and protection have been REMOVED with railML® version 2.4 since they were not useful for many applications.

Best practice & Examples / Empfohlene Anwendung & Beispiele

Consider railML® 2.3 example of Middle Rhine Railway by GPSinfradat (link to the railML® website).

View/edit list on the separate source page.

LineID TrackID Type LevelCrossing Name AbsPos Lat Lon
2630 1 LzHH BÜ LzHH Brunnenstraße 97740 50,294743 7,600783

This code example defines a <levelCrossing> of the Middle Rhine Railway.

<levelCrossings>
  <levelCrossing id="lc263011" pos="6690" name="BÜ LzHH Brunnenstraße" absPos="97740" xml:lang="de">
    <geoCoord coord="50.294743 7.600783" epsgCode="urn:ogc:def:crs:EPSG::4326"/>
    <crossedElements>
      <crossedElement id="cELC263011" pos="6690" name="LzHH Brunnenstraße" type="highway:road" xml:lang="de"/>
    </crossedElements>
  </levelCrossing>
…
</levelCrossings>

Notes / Anmerkungen

Meaning of pos, absPos, offset and length

General information on positioning

Positive pos values describe the distance from the track's begin. The track length is derived from the pos value in <trackEnd>.

The absolute mileage refered to by absPos is usually found on technical drawings of the track layout or on mileage posts next to the track.

If an offset is specified, also a length needs to be provided, otherwise offset cannot be interpreted and should be ignored.

If an absPos is specified, it is also shifted by a specified offset. The same rules apply as for the pos. This also means that if no offset is specified, pos as well as absPos describe the center of the <levelCrossing>.

Open issues / Offene Punkte/Pendenzen

Not yet described. / Noch nicht beschrieben.