SIST EN ISO 19148:2012
(Main)Geographic information - Linear referencing (ISO 19148:2012)
Geographic information - Linear referencing (ISO 19148:2012)
This International Standard shall: Provide means to geo reference information to any linear features like wiring, pipelines, shorelines, rivers, roads, rails, seaways and other linear infrastructures by suggesting a model for a common Linear Referencing System, "LRS".
Geoinformation - Standortbezogene Dienste - Lineares Bezugssystem (ISO 19148:2012)
Diese Internationale Norm legt ein konzeptuelles Schema für Orte in Bezug zu einem eindimensionalen
Objekt als Messung entlang (und optional versetzt zu) diesem Objekt fest. Sie definiert eine Beschreibung der
Daten und Operationen, die zur Anwendung und Unterstützung der linearen Referenzierung erforderlich sind.
Diese Internationale Norm ist anwendbar auf Transport- und Versorgungsdienste, ortsbezogene Dienste
sowie sonstige Anwendungen, die Orte in Bezug zu linearen Objekten definieren.
Information géographique - Références linéaires (ISO 19148:2012)
L'ISO 19148:2011 spécifie un schéma conceptuel pour les localisations par rapport à un objet à une seule dimension sous la forme d'un mesurage le long de cet objet (et éventuellement décalées par rapport à celui-ci). Elle définit une description des données et des opérations nécessaires pour utiliser et prendre en charge les référencements linéaires.
Elle est applicable aux transports, aux installations, aux services géolocalisés et aux autres applications qui définissent des localisations par rapport à des objets linéaires.
Geografske informacije - Linearno georeferenciranje (ISO 19148:2012)
Ta mednarodni standard določa zasnovno shemo za lokacije glede na enodimenzionalni predmet kot merjenje vzdolž (in neobvezno izravnano od) tega predmeta. Določa opis podatkov in operacij, potrebnih za uporabo in podporo linearnega georeferenciranja. Ta mednarodni standard se uporablja za prevoz, pomožna sredstva, lokacijsko odvisne storitve in druge aplikacije, ki določajo lokacije glede na linearne predmete.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 19148:2012
01-maj-2012
Geografske informacije - Linearno georeferenciranje (ISO 19148:2012)
Geographic information - Linear referencing (ISO 19148:2012)
Geoinformation - Standortbezogene Dienste - Lineares Bezugssystem (ISO 19148:2012)
Information géographique - Références linéaires (ISO 19148:2012)
Ta slovenski standard je istoveten z: EN ISO 19148:2012
ICS:
07.040 Astronomija. Geodezija. Astronomy. Geodesy.
Geografija Geography
35.240.70 Uporabniške rešitve IT v IT applications in science
znanosti
SIST EN ISO 19148:2012 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 19148:2012
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SIST EN ISO 19148:2012
EUROPEAN STANDARD
EN ISO 19148
NORME EUROPÉENNE
EUROPÄISCHE NORM
February 2012
ICS 35.240.70
English Version
Geographic information - Linear referencing (ISO 19148:2012)
Information géographique - Référencement linéaire (ISO Geoinformation - Lineares Bezugssystem (ISO
19148:2012) 19148:2012)
This European Standard was approved by CEN on 21 January 2012.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same
status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2012 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 19148:2012: E
worldwide for CEN national Members.
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SIST EN ISO 19148:2012
EN ISO 19148:2012 (E)
Contents Page
Foreword .3
2
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SIST EN ISO 19148:2012
EN ISO 19148:2012 (E)
Foreword
This document (EN ISO 19148:2012) has been prepared by Technical Committee ISO/TC 211 "Geographic
information/Geomatics" in collaboration with Technical Committee CEN/TC 287 “Geographic Information” the
secretariat of which is held by BSI.
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by August 2012, and conflicting national standards shall be withdrawn at
the latest by August 2012.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland, Turkey and the United Kingdom.
Endorsement notice
The text of ISO 19148:2012 has been approved by CEN as a EN ISO 19148:2012 without any modification.
3
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SIST EN ISO 19148:2012
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SIST EN ISO 19148:2012
INTERNATIONAL ISO
STANDARD 19148
First edition
2012-02-15
Geographic information — Linear
referencing
Information géographique — Référencement linéaire
Reference number
ISO 19148:2012(E)
©
ISO 2012
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SIST EN ISO 19148:2012
ISO 19148:2012(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2012
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
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Published in Switzerland
ii © ISO 2012 – All rights reserved
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SIST EN ISO 19148:2012
ISO 19148:2012(E)
Contents Page
Foreword . iv
Introduction . v
1 Scope . 1
2 Conformance . 1
2.1 Conformance overview . 1
2.2 Conformance classes . 2
3 Normative references . 3
4 Terms and definitions . 3
5 Abbreviated terms . 6
6 Linear referencing . 6
6.1 Introduction . 6
6.2 Package: Linear Referencing System . 17
6.3 Package: Linear Referencing Towards Referent . 31
6.4 Package: Linear Referencing Offset . 33
6.5 Package: Linear Referencing Offset Vector . 39
6.6 Package: Linearly Located Event . 41
6.7 Package: Linear Segmentation . 47
Annex A (normative) Abstract test suite . 52
Annex B (informative) Generalized model for linear referencing . 56
Annex C (informative) Commonly used linear referencing methods and models . 59
Annex D (informative) Event and segmentation examples . 79
Bibliography . 86
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SIST EN ISO 19148:2012
ISO 19148:2012(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 19148 was prepared by Technical Committee ISO/TC 211, Geographic information/Geomatics.
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SIST EN ISO 19148:2012
ISO 19148:2012(E)
Introduction
This International Standard is a description of the data and operations required to support linear referencing.
This includes Linear Referencing Systems, linearly located events and linear segments.
Linear Referencing Systems enable the specification of positions along linear objects. The approach is based
[3]
upon the Generalized Model for Linear Referencing first standardized within ISO 19133:2005, 6.6. This
International Standard extends that which was included in ISO 19133, both in functionality and explanation.
ISO 19109 supports features representing discrete objects with attributes having values which apply to the
entire feature. ISO 19123 allows the attribute value to vary, depending upon the location within a feature, but
does not support the assignment of attribute values to a single point or length along a linear feature. Linearly
located events provide the mechanism for specifying attribution of linear objects when the attribute value
varies along the length of a linear feature. A Linear Referencing System is used to specify where along the
linear object each attribute value applies. The same mechanism can be used to specify where along a linear
object another object is located, such as guardrail or a traffic accident.
It is common practice to segment a linear object having linearly located events, based upon one or more of its
attributes. The resultant linear segments are attributed with just the attributes used in the segmentation
process, insuring that the linear segments are homogeneous in value for these segmenting attributes.
This International Standard differs from ISO 19133:2005, 6.6 in the following areas.
a) All occurrences of Linear Reference Method and Linear Reference System have been changed to Linear
Referencing Method and Linear Referencing System, respectively.
b) LR_Element has been renamed LR_LinearElement and further defined as being a feature or geometry or
topology. These shall support the newly introduced interface ILinearElement, meaning that it is possible
to measure (linearly) along them.
c) The newly introduced ILinearElement interface includes operations for returning the default Linear
Referencing Method of the linear element and any of its length or weight attribute values. It also includes
operations for translating between Linear Referencing Methods and/or linear elements.
d) The types of Linear Referencing Methods have been formalized as a CodeList. Names of common Linear
Referencing Methods have been added as an informative annex.
e) An additional attribute, constraint[0.*], has been added to Linear Referencing Method to specify the
constraints imposed by the method, such as “only allows reference marker referents”. This is an
alternative to subtyping the methods that would force a too-structured approach, inconsistent with the
Generalized Model, and would be indeterminate due to the wide variety of Linear Referencing Methods
currently in use.
f) The Linear Referencing Method “project” operation has been renamed “lrPosition” and moved to the
ISpatial interface and a second, opposite, operation “point” has been added. Only LR_Curves realize this
interface since their spatial representation is requisite for the two operations, along with the
ILinearElement interface.
g) The LR_PositionExpression measure attribute has been extracted out into a Distance Expression along with
the optional referent and offset roles consistent with the original theoretical model. This allows for specifying
only an LR_DistanceExpression when the LR_LinearElement and LR_LinearReferencingMethod are
already known.
h) Reference Marker has been generalized to LR_Referent to enable support for other referent types such
as intersections, boundaries and landmarks. This type has been formalized as a CodeList.
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ISO 19148:2012(E)
i) A second, optional (towards) Referent has been added in a new (optional) package, Linear Referencing
Towards Referent (LRTR), for those Linear Referencing Methods which allow this to disambiguate
measurement direction.
j) Lateral Offsets have been moved to a new (optional) package, Linear Referencing Offset (LRO).
Horizontal, vertical, and combined horizontal and vertical offsets are now supported. Offset referent has
been generalized to allow for feature instances as well as character strings.
k) Vector Offsets have been adopted from ISO 19141. They exist in a new (optional) package, Linear
Referencing Offset Vector (LROV). An optional offset vector Coordinate Reference System (CRS) can be
provided if it is different from the CRS of the linear element.
l) The theoretical model on which the original standard was built is explained in Annex B.
m) More descriptive text is added throughout this International Standard to explain the concepts being
presented.
n) Minor changes to some class, attribute and role names have been made.
o) A new (optional) package, Linearly Located Event (LE) has been added which uses linearly referenced
positions to specify where along a linear feature a particular attribute value or other feature instance
applies.
p) A new (optional) package, Linear Segmentation (LS) has been added to support the generation of
homogeneous attributed linear segments from linear features with length-varying attribution.
q) Absolute Linear Referencing Method with non-zero linear element start is now accommodated.
r) lateralOffsetReferentType and verticalOffsetReferentType have been changed from CodeLists to
Character Strings.
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SIST EN ISO 19148:2012
INTERNATIONAL STANDARD ISO 19148:2012(E)
Geographic information — Linear referencing
1 Scope
This International Standard specifies a conceptual schema for locations relative to a one-dimensional object
as measurement along (and optionally offset from) that object. It defines a description of the data and
operations required to use and support linear referencing.
This International Standard is applicable to transportation, utilities, location-based services and other
applications which define locations relative to linear objects.
2 Conformance
2.1 Conformance overview
Clause 6 of this International Standard uses the Unified Modelling Language (UML) to present conceptual
schemas for describing the constructs required for Linear Referencing. These schemas define conceptual
classes that shall be used in application schemas, profiles and implementation specifications. This
International Standard concerns only externally visible interfaces and places no restriction on the underlying
implementations other than what is required to satisfy the interface specifications in the actual situation, such
as
interfaces to software services using techniques such as SOAP;
interfaces to databases using techniques such as SQL;
data interchange using encoding as defined in ISO 19118.
Few applications require the full range of capabilities described by this conceptual schema. Clause 6,
therefore, defines a set of conformance classes that support applications whose requirements range from the
minimum necessary to define data structures to full object implementation. This flexibility is controlled by a set
of UML types that can be implemented in a variety of manners. Implementations that define full object
functionality shall implement all operations defined by the types of the chosen conformance class, as is
common for UML designed object implementations. It is not necessary for implementations that choose to
depend on external “free functions” for some or all operations, or forgo them altogether, to support all
operations, but they shall always support a data type sufficient to record the state of each of the chosen UML
types as defined by its member variables. It is acceptable to use common names for concepts that are the
same but have technically different implementations. The UML model in this International Standard defines
abstract types, application schemas define conceptual classes, various software systems define
implementation classes or data structures, and the XML from the encoding standard (ISO 19118) defines
entity tags. All of these reference the same information content. There is no difficulty in allowing the use of the
same name to represent the same information content even though at a deeper level there are significant
technical differences in the digital entities being implemented. This “allows” types defined in the UML model to
be used directly in application schemas.
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SIST EN ISO 19148:2012
ISO 19148:2012(E)
2.2 Conformance classes
2.2.1 General
Conformance to this International Standard shall consist of either data type conformance or both data type
and operation conformance.
2.2.2 Data type conformance
Data type conformance includes the usage of data types in application schemas or profiles that instantiate
types in this International Standard. In this context, “instantiate” means that there is a correspondence
between the types in the appropriate part of this International Standard, and the data types of the application
schema or profile in such a way that each standard type can be considered as a supertype of the application
schema data type. This means that an application schema or profile data type corresponding to a standard
type contains sufficient data to recreate that standard type's information content.
Table 1 assigns conformance tests to each of the packages in Clause 6. Each row in the table represents one
conformance class. A specification claiming data type conformance to a package in the first column of the
table shall satisfy the requirements specified by the tests given in the remaining columns to the right.
Table 1 — Data type conformance tests
Conformance test
Package
A.1.1 A.1.2 A.1.3 A.1.4 A.1.5 A.1.6
Linear Referencing System X — — — — —
Linear Referencing Towards Referent X X — — — —
Linear Referencing Offset X — X — — —
Linear Referencing Offset Vector X X X
— — —
Linearly Located Event X — — — X —
Linear Segmentation X — — — X X
2.2.3 Operation conformance
Operation conformance includes both the consistent use of operation interfaces and data type conformance
for the parameters, and return values used by those operations. Operation conformance also includes get and
set operations for attributes.
Table 2 assigns conformance tests to each of the packages in Clause 6. Each row in the table represents one
conformance class. A specification claiming operation conformance to a package in the first column of the
table shall satisfy the requirements specified by the tests given in the remaining columns to the right.
Table 2 — Operation conformance tests
Conformance test
Package
A.1.1 A.1.2 A.1.3 A.1.4 A.1.5 A.1.6
A.2.1 A.2.2 A.2.3 A.2.4 A.2.5 A.2.6
Linear Referencing System X — — — — —
Linear Referencing Towards Referent X X — — — —
Linear Referencing Offset X — X — — —
Linear Referencing Offset Vector X X X
— — —
Linearly Located Event X — — — X —
Linear Segmentation X — — — X X
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ISO 19148:2012(E)
3 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO/TS 19103, Geographic information — Conceptual schema language
ISO 19107, Geographic information — Spatial schema
ISO 19108, Geographic information — Temporal schema
ISO 19111, Geographic information — Spatial referencing by coordinates
4 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
4.1
attribute event
value of an attribute of a feature (4.4) that may apply to only part of the feature
NOTE 1 An attribute event includes the linearly referenced location (4.16) where the attribute value applies along the
attributed feature (4.2).
NOTE 2 An attribute event may be qualified by the instant (4.8) in which, or period (4.20) during which, the attribute
value applied.
4.2
attributed feature
feature (4.4) along which an attribute event (4.1) applies
4.3
direct position
position (4.21) described by a single set of coordinates within a coordinate reference system
[ISO 19107:2003, 4.26]
4.4
feature
abstraction of real world phenomena
[ISO 19101:2002, 4.11]
4.5
feature event
information about the occurrence of a located feature (4.17) along a locating feature (4.18)
NOTE 1 A feature event includes the linearly referenced location (4.16) of the located feature along the locating
feature.
NOTE 2 A feature event may be qualified by the instant (4.8) in which, or period (4.20) during which, the feature event
occurred.
4.6
geometric primitive
geometric object representing a single, connected, homogeneous element of space
[ISO 19107:2003, 4.48]
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4.7
height
h, H
distance of a point from a chosen reference surface measured upward along a line perpendicular to that
surface
[ISO 19111:2007, 4.29]
NOTE The surface is normally used to model the surface of the Earth.
4.8
instant
0-dimensional geometric primitive (4.6) representing position (4.21) in time
[ISO 19108:2002, 4.1.17]
NOTE The geometry of time is discussed in ISO 19108:2002, 5.2.
4.9
linear element
1-dimensional object that serves as the axis along which linear referencing (4.10) is performed
NOTE Also known as curvilinear element.
EXAMPLES Feature (4.4), such as “road”; curve geometry; directed edge topological primitive.
4.10
linear referencing
specification of a location (4.19) relative to a linear element (4.9) as a measurement along (and optionally
offset from) that element
NOTE An alternative to specifying a location as a two- or three- dimensional spatial position (4.22).
4.11
Linear Referencing Method
manner in which measurements are made along (and optionally offset from) a linear element (4.9)
4.12
Linear Referencing System
[1]
set of Linear Referencing Methods (4.11) and the policies, records and procedures for implementing them
4.13
linear segment
part of a linear feature (4.4) that is distinguished from the remainder of that feature by a subset of attributes,
each having a single value for the entire part
NOTE 1 A linear segment is a one-dimensional object without explicit geometry.
NOTE 2 The implicit geometry of the linear segment can be derived from the geometry of the parent feature.
4.14
linearly located
located using a Linear Referencing System (4.12)
4.15
linearly located event
occurrence along a feature (4.4) of an attribute value or another feature
NOTE 1 The event location (4.19) is specified using linearly referenced locations (4.16).
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NOTE 2 A linearly located event may be qualified by the instant (4.8) in which, or period (4.20) during which, the
linearly located event occurred.
NOTE 3 ISO 19108 limits events to a single instant in time and does not include the specification of a location.
4.16
linearly referenced location
location whose position (4.21) is specified using linear referencing (4.10)
4.17
located feature
feature (4.4) that is linearly located (4.14) along an associated (locating) feature
EXAMPLE A feature “bridge” may be a located feature along the feature “railway” [a locating feature (4.18)].
4.18
locating feature
feature (4.4) that is used to identify the location (4.19) of linearly located (4.14) features
EXAMPLE A feature “road” may be the locating feature for a feature “pedestrian crossing” [a located feature (4.17)].
4.19
location
identifiable geographic place
[ISO 19112 :2003, 4.4]
NOTE A location is represented by one of a set of data types that describe a position (4.21), along with metadata
about that data, including coordinates (from a coordinate reference system), a measure [from a Linear Referencing
System (4.12)], or an address (from an address system). [ISO 19133].
4.20
period
one-dimensional geometric primitive (4.6) representing extent in time
[ISO 19108:2002, 4.1.27]
NOTE A period is bounded by two different temporal positions (4.23).
4.21
position
data type that describes a point or geometry potentially occupied by an object or person
[ISO 19133:2005, 4.18]
NOTE A direct position (4.3) is a semantic subtype of position. Direct positions as described can define only a point
and, therefore, not all positions can be represented by a direct position. That is consistent with the “is type of” relation. An
ISO 19107 geometry is also a position, just not a direct position.
4.22
spatial position
direct position (4.3) that is referenced to a 2- or 3-dimensional coordinate reference system
NOTE An alternative to specifying a location (4.19) as a linearly referenced location (4.16).
4.23
temporal position
location (4.19) relative to a temporal reference system (4.24)
[ISO 19108:2002, 4.1.34]
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4.24
temporal reference system
reference system against which time is measured
[ISO 19108:2002, 4.1.35]
4.25
valid time
time when a fact is true in the abstracted reality
[ISO 19108:2002, 4.1.39]
5 Abbreviated terms
CRS Coordinate Reference System
LRM Linear Referencing Method
LRS Linear Referencing System
SOAP Single Object Access Protocol
SQL Structured Query Language
UML Unified Modelling Language
XSP Cross-Sectional Positioning
NOTE The UML notation described in ISO/TS 19103 is used in this International Standard.
6 Linear referencing
6.1 Introduction
6.1.1 Linear referencing concepts
6.1.1.1 General
Linear Referencing Systems are in wide use in transportation but are also appropriate in other areas such as
utilities. They allow for the specification of positions along linear elements by using measured distances along
(and optionally offset from) the element. This is in contrast to using spatial positions that use two- or three-
dimensional coordinates, consistent with a particular Coordinate Reference System (CRS).
Linearly referenced locations are significant for several reasons. First, a significant amount of information is
currently held in huge databases from legacy systems that pre-date Geographic Information Systems (GIS).
Many useful applications can and have been built on these data with no understanding of where on the earth's
surface the data are located. Knowing where they are located relative to a linear element such as a roadway
route or pipeline is sufficient to support these applications and can be used as a means of integrating data
from multiple, disparate sources.
In some situations, having a linearly referenced location along a known linear element is more advantageous
than knowing its spatial position. Consider a crash in need of emergency assistance
...
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