Motivation

As described in this Brief introduction to ISO 19148 and ISO 19156,

ISO 19148 was designed in order to express locations along a linear object,

and

ISO 19156 was designed in order to describe observations, measurements and samples.

The motivation to connect ISO 19148 and ISO 19156 is to have the capacity to describe observations, measurements and samples that are linear referenced. In geotechnics, one major use case for that is borehole data.

Methodology

In order to explain our approach toward integrating the concepts from Linear Referencing (ISO 19148) with parallel concepts from the Sampling part of Observations, Measurements and Samples (ISO 19156), we start with an example provided with the Linear Referencing standard. When specifying a feature located along a linear feature, 19148 utilizes the FeatureEvent Class. This Event references:

• the linear feature under consideration. Association role: linearElement
• information where along this linear feature (distance relative to the origin of the linear feature) the linearly referenced feature is located (this can be a point or interval. dataTypes AtLocation and FromToLocation provided for this information). Association role: location
• the linearly referenced feature, located along the linear feature. Association role: locatedFeature In the example provided with 19148, a wildlife fence is located at a specific position along a road (from meter 0 to meter 5), leading to the following UML:

In a first step, the same structure was used, but the classes from the example were replaced by examples relating to boreholes and sampling a segment of this borehole. In addition, where relevant, Interfaces from the OMS model were added, in order to show the alignment between the interfaces from Linear Referencing with those from OMS. Class replacements were as follows:

• FT Road: BH_Trajectory
• FT WildlifeFence: BH_Segment

This brings us to the following UML:

In this diagram, the parallel between the linear referencing FeatureEvent and the OMS Sampling become apparent, as well as the fact that the linear referencing locatedFeature corresponds with the OMS Sample. In addition, the location information is related to the OMS SamplingProcedure.

However, when dealing with boreholes, it is common to provide information on the borehole collar, to indicate the start of the borehole (as well as to provide additional information on the borehole). The linear referencing model foresees the Referent Interface to provide the origin of the linear feature. Integrating a BH_Collar featureType into the model above leads us to the following final level of the conceptual linear borehole model: