=Paper= {{Paper |id=Vol-2636/01paper |storemode=property |title=From obXML to the OP ontology: developing a semantic model for occupancy profile |pdfUrl=https://ceur-ws.org/Vol-2636/01paper.pdf |volume=Vol-2636 |authors=Serge Chavez-Feria,Giorgos Giannakis,Raul García-Castro,María Poveda-Villalón |dblpUrl=https://dblp.org/rec/conf/ldac/Chavez-FeriaGGP20 }} ==From obXML to the OP ontology: developing a semantic model for occupancy profile== https://ceur-ws.org/Vol-2636/01paper.pdf
    Proceedings of the 8th Linked Data in Architecture and Construction Workshop - LDAC2020




From obXML to the OP Ontology: Developing a
    Semantic Model for Occupancy Profile?

        Serge Chávez-Feria1[0000−0002−7454−9202] , Giorgos Giannakis2 , Raúl
                  Garcı́a-Castro1[0000−0003−3587−0367] , and Marı́a
                       Poveda-Villalón1[0000−0003−3587−0367]
        1
             Ontology Engineering Group, Universidad Politécnica de Madrid, Spain
            serge.chavez.feria@upm.es, rgarcia@fi.upm.es, mpoveda@fi.upm.es
                                   2
                                     Hypertech, Greece
                                g.giannakis@hypertech.gr



            Abstract. Building energy performance simulation is vital for predict-
            ing energy performance under specific conditions. Even though there
            exist several calculation methodologies that can provide precise simula-
            tion approximations, the accuracy of these tools is affected by the level of
            detail of its input data, being occupant behavior the main source of un-
            certainty in building energy performance results. Hence, initiatives such
            as the obXML schema have been developed recently to get a deeper un-
            derstanding and to generate a more elaborated description of these data.
            Besides, the use of semantic web technologies can open opportunities
            to link behavioral patterns with other building information and related
            domains allowing interoperability and heterogeneous data integration.
            This paper presents the Occupancy Profile ontology, a semantic model
            based on obXML that allows the representation of occupant behaviors
            and actions inside building spaces. This paper also provides a catalogue
            of modelling decisions taken during the development and an example.

            Keywords: Ontological Engineering · Occupancy Profile · Semantics.


1      Introduction
The usage of building energy performance simulation has gained significant at-
tention recently that stems from its capability to accurately predict the energy
performance of the building sector under specific conditions. Among a wide range
of calculation methodologies, the 3D zonal-type simulation approximation is fre-
quently adopted in many envisaged and practical use scenarios, as it manages to
strike a balance between accuracy and computational complexity. However, the
accuracy of a 3D zonal-type simulation is highly affected by the level of detail of
its input data. Static data include the building geometry, construction materials,
glazing information, systems used in the building, etc., while dynamic data con-
sist of all time-dependent data such as user-actions (e.g. opening and closing the
?
    Supported by the BIMERR project funded from the European Union’s Horizon 2020
    research and innovation programme under grant agreement no. 820621.



      Copyright © LDAC2020 for this paper by its authors. Use permitted under Creative
      Commons License Attribution 4.0 International (CC BY 4.0).




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windows), occupancy schedules in each of the building zones, use of equipment,
weather predictions, etc., commonly being in-building sensed measurements.
    In recent studies [4], dynamic data, widely known as Occupant Behaviour
(OB), has been criticized as the major cause of uncertainty in building energy
performance results. Despite its stochastic nature, in common practice OB is
oversimplified and introduced to the 3D zonal-type simulation engines as either
deterministic or predefined rule-based schedules, ignoring that way the OB di-
versity [2]. Hence, having a deeper understanding and properly modeling the
occupant behavior have been of paramount importance within IEA EBC Annex
66, where data, methods and models have been developed and applied to un-
derstand and reduce the gap between simulated and measured building energy
performance by representing OB in a standardized XML schema (obXML).
    In the context of the H2020 European project BIMERR,3 the consortium
leverages the outcomes of the Annex 66,4 adapting the obXML data model to
an OWL ontology representation. The new ontology is then used to project
occupancy profiles, which mimic building residents actions, and building system
utilization boundaries. By means of this representation, occupancy data can
be shared among the different applications of the project, fostering semantic
interoperability by semantically linking with other domains from the BIMERR
ontology network.
    In the present work, after explaining the context of the Occupancy Profile
ontology within the BIMERR project (Section 2), and the methodology followed
(Section 3), the OP ontology, is introduced (Section 4). An example of use is
provided (Section 5) before presenting some conclusions and future lines of work
(Section 7).


2      BIMERR Project Context

The BIMERR project aims to design and implement a set of Building Infor-
mation Modelling tools to facilitate the development of building renovations
projects. The suite of tools involved in the project includes a decision support
system that guides designers in the election of the best renovation scenario tak-
ing into account different aspects of the building. These tools range from laser
scanners that automatically generate a 3D representation of the existing build-
ing to process management tools that are constantly monitoring the planning
and execution of the renovation activities. Due to this high diversity of tools, the
core of the system need an interoperability layer that support the flow of infor-
mation between the applications. Such central component data model is driven
by a network of ontologies where each modules covers an specific domain within
the building sector.
   In this context, one of the key modules in the network is the OP ontology,
which is utilized to define residents profiles and their interactions with building
3
    https://bimerr.eu/
4
    https://annex66.org/




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system. This information is then needed to make better estimations of building
energy performance for each renovation option simulated by the system.


3   Methodological background

The OP ontology has been built following the LOT (Linked Open Terms)
methodology, proposed in [8] and further developed at [3]. This methodology
focuses on: a) the reuse of already published vocabularies or ontologies and b)
the online publication of the built ontology in several formats according to the
Linked Data principles.
    The LOT methodology defines iterations over a basic workflow composed
of the following activities: 1) ontological requirements specification; 2) ontol-
ogy implementation; 3) ontology publication; and 4) ontology maintenance. The
activities, roles involved and expected outputs are depicted in Figure 1.


    § Ont. Devel.                                                                                         § Ont. Devel.
    § Users                                  § Ont. Devel.                    § Ont. Devel.               § Users
    § Experts                                                                                             § Experts

     Ont. requirements                          Ontology                         Ontology                  Ontology
       specification                         implementation                     Publication               maintenance


                            Ontology
                                                   Encoding      Evaluation       Online
          ORSD           conceptualization                                                                    Issue tracker
                                                                                 ontology
                             Ontology              Ontology      Validated
                              model                 code         ontology     Legend
                                                                                              activity flow

                                                Ontology reuse                 § Actor         Activity          Output




        Fig. 1: LOT methodology base workflow. Image adapted from [3].


    The goal of the ontology requirements specification activity is to col-
lect the requirements that the ontology should fulfill [10]. These requirements
are usually grouped as: a) non-functional (purpose, scope, domain, ontology im-
plementation language, etc.) and b) functional (explicit knowledge that should
be capture by the ontology). As input for this activity, the LOT methodology
propose domain experts and ontology users (e.g., software developers) to share
with the ontology development team documents like manuals, API specifications,
data samples, standards, formats used in the community, etc.
    Taking as input the ORSD (Ontology Requirement Specification Document),
the main goal of the ontology implementation activity is to build the on-
tology using a formal implementation language [10]. LOT proposes to run this
phase in different sprints in which a set of requirements are selected to be im-
plemented and an ontology version is produced after each sprint. The ontology
implementation is divided into the following sub-activities:

 – During the ontology conceptualization developers organize and structure
   the information gathered in the ORSD to build meaningful models at the
    Proceedings of the 8th Linked Data in Architecture and Construction Workshop - LDAC2020




   knowledge [10].During this activity ontology developers could different tools
   as diagrams (for example, UML based) or description logics to create the
   model according to the requirements previously acquired.
 – The ontology encoding activity refers to the translation of the conceptual-
   ization into one or more ontologies formalized in OWL.
 – Ontology reuse refers to the process of using available ontologies for solving
   different problems [10].
 – Evaluation. This activity refers to checking the technical quality of an on-
   tology against a frame of reference [10]. For doing so, some evaluation criteria
   should be selected for example: domain coverage, fit for application, detection
   of bad practices, logical consistency, etc. ) [9] for bad practices detection.

    The goal of the ontology publication activity is to make the ontology
available on-line both as human-readable documentation and in one or more
machine-readable formats. Content negotiation mechanisms should be establish
so that every version of the ontology is reachable from its URI.
    Finally, the goal of the ontology maintenance activity is to update the
ontology after the last release.


4      Occupancy profile ontology development

This section details how each step of the methodological background was applied
for the development of the Occupancy Profile Ontology and the particular steps
and decisions made to achieve a semantic representation of the domain.


4.1     Requirements Specification for the OP Ontology

The goal of the OP ontology is to provide an ontological representation of the oc-
cupant behaviour domain. Therefore, outputs from the Annex 66 project, which
aimed to understand the impact of occupant behavior in energy building con-
sumption, were taken as input. More precisely, the following documents were con-
sidered during the ontology requirements specification activity: a) the obXML
V1.3.3 specification provided by “Occupant Behavior Research at LBNL BTUS”
5
  ; b) research papers about obXML [6] and [5]; and c) data provided by experts
and “Occupant Behavior Research at LBNL BTUS”.
     From the obXML and associated documentation, we created three tables with
a set of initial functional requirements, following the intermediate representations
proposed by METHONTOLOGY. The first table handles the main concepts of
the domain, the second table the relationships identified between concepts, and
the last table the attributes that describe certain aspect of the concepts by means
of literals.
5
    Available of https://behavior.lbl.gov/




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4.2     Implementation of the OP Ontology

For this activity, the requirements obtained from the previous step were taken
to propose a first draft of the conceptualization. This initial conceptualization,
shown in Figure 2, represents concepts as classes, relations between main con-
cepts in the form of object properties, and attributes in the form of datatype
properties, providing the model with an OWL representation. Note that for
readability purposes, Figure 2 does not show all attributes and terminology de-
scribed in obXML, but only the main entities. The figure includes also a legend
explaining the meaning of the graphics that will be used along this paper.
    Even though obXML gives the main resources to model the domain, the
constructs available in an XML schema are not directly mapped to OWL con-
structs, therefore some modelling decisions should be made by ontology engineers
to transform obXML into an ontology compliant to the OWL semantics (while
keeping a OWL-DL complexity). For this reason, the initial conceptualization in
Figure 2 should be reviewed by ontology engineers to make modelling decisions
and modifications. Along this section the main Ontological Modelling Decisions
(OMD) are described and identified in the following way “(OMDX)” where X is
the number of the decision and links the explanation to: (a) the initial situation:
numerated dashed (red) ellipses in Figure 2 and (b) current situation: numerated
dashed (green) ellipses in Figure 3.

rdfs         http://www.w3.org/2000/01/rdf-schema#
owl          http://www.w3.org/2002/07/owl#
foaf         http://xmlns.com/foaf/0.1/
xsd          http://www.w3.org/2001/XMLSchema#
saref        https://saref.etsi.org/core/
s4bldg       https://w3id.org/def/saref4bldg#
op           https://bimerr.iot.linkeddata.es/def/occupancy-profile#
building     https://bimerr.iot.linkeddata.es/def/building#
time         http://www.w3.org/2006/time#
skos         http://www.w3.org/2004/02/skos/core#



    The first decision about ontology engineering was related to the ontology
reuse activity. In this case, as no ontology covering the OP domain was known
nor found in ontology registries such as LOV,6 the decision made was to develop
a first ontology conceptualization based on obXML and then to look for subsets
of it that could be covered by or aligned to standard or well-known ontologies. In
the opposite case, when ontologies covering the domain of discourse are found,
the draft conceptualization may be created considering the ontology concepts
and relations to be reused. Note that Figure 2 shows some concepts defined
in the namespace “building”, which means that those entities come from the
Building module of the BIMERR ontology network. For the rest of the paper
the namespaces in the box above will be used.
    The purpose of the OP ontology is the representation of occupant behav-
ior inside building spaces, and their interactions with energy-related building
systems. Hence, the whole conceptualization builds around the root concepts
6
    Linked Open Vocabularies https://lov.linkeddata.es




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    Fig. 2: Initial Conceptualization of the Occupancy Profile Ontology




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building, space, behavior, occupant, system, and action. Building and Space are
concepts pertaining to the building module of the BIMERR ontology network,
however they also play an important role within the occupancy profile context.
In the conceptualization we reuse the classes created for the Building ontology,7
which at the same time reuse and are aligned with some well know ontologies in
the LBD community such as BOT,8 or SAREF4BLDG.9
    The building:Space concept was extended in its initial definition to sup-
port the specification of the number of occupants inside spaces, feature that
is important from the occupancy perspective. This extension involves the at-
tributes op:maxNumberOccupants and op:minNumberOccupants. It also should
be mentioned that we eliminated the initial concepts referring to building types
(OMD1) and space types (OMD2). These concepts were originally considered
to support specific taxonomies provided within the obXML schema, however,
as RDF(S), and therefore OWL, provides a construct with specific semantics to
build taxonomies, we decided to include them as hierarchies of classes under the
concepts building:Building and building:Space respectively (indicated but
not added in Figure 3), without losing expressiveness in the model.
    A space may contain several systems that occupants can interact with to
adjust their comfort requirements. The obXML schema provides an initial list
of systems. Instead of creating a new class to allocate such list, we reuse con-
cepts available in SAREF and SAREF4BLDG (OMD3). For instance, for HVAC
equipment we used the concept saref:HVAC, subclass of saref:Device and
s4bldg:PhysicalObject. For building objects not supported in SAREF4BLDG,
new concepts are created, for example op:LightingDevice. The link between a
space and those systems is achieved by the property s4bldg:contains, which
connects a building space to individuals of the class s4bldg:PhysicalObject.
The relation between systems and their respective control type is modeled by
means of the property op:hasOperationalMode (OMD4). The obXML docu-
mentation provides a list of control options that is represented in the model by
the class op:OperationalModeConcept, subclass of the concept skos:Concept.
This modelling decision is recurrent with concepts that gather types. For the
op:ControlType case, the list of “types” could lead either to a class hierarchy or
to an enumeration class. A particular case of the latter is modelling this enumer-
ations in a richer way following the SKOS model [1] as it allows us to relate the
created instances by means of the properties skos:narrower or skos:broader
among others. The decision was to keep the main hierarchy based on device
functions (e.g. thermostat, light, etc.), as it is a more natural classification than
based on the control type, and to model the control types as SKOS as it allows
for a richer expressivity than an enumerated class.
    obXML describes an occupant as a particular person instead of a general
profile. It means, an instance of op:Occupant has a particular name and age. For
this reason it has been aligned with the foaf:Person class. Albeit, attributes like
7
  http://bimerr.iot.linkeddata.es/def/building
8
  https://w3id.org/bot
9
  https://w3id.org/def/saref4bldg




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op:age are not critical or even used for energy calculation, they would be useful
to generate a direct mapping with obXML. As the attribute op:age changes
constantly over time, we incorporate the additional attribute op:birthDate for a
more resilient model (OMD5). See that this attribute has to be created because
the FOAF relation to the birth does not include the year, only day and month,
and obXML represents the age, for what the year is needed.
    An occupant can have several behaviors with respect to the environmental
conditions within a building space. A behavior can lead to an action over a
system or a passive acceptance of the uncomfortable conditions. This is mod-
eled by the link op:leadsTo that connects to union of individuals of the classes
op:Action and op:Inaction (OMD6). Although obXML models Inaction as
being a children element of Action, we preferred to represent them as disjoint
classes because the semantic of both concepts is completely different. That is,
having “inaction” as subclass of “action” might seem contradictory. The option
to link from a behavior to an action or inaction is given by an existential con-
straint defined for the class op:Behavior over the property op:leadsTo which
can take values of op:Action or op:Inaction
    One important aspect in occupant behavior is the stochasticity involved
in human-system interaction. The way to model this interaction occur-
rence probability is through mathematical formulas, represented in the model
by op:InteractionFormula. As part of the modelling decisions, we group
together mathematical formulas into general templates instead of specify-
ing the exact dimensionality of them. The user of the model can define
multidimensional equations through the properties op:hasCoefficient and
op:hasIndependentVariable. The main purpose of the equations is to represent
the probability of the occupants to interact with systems given a set of environ-
mental factors. In this context, the range of op:hasIndependentVariable is the
concept op:EnvironmentalParameter that describes certain physical properties
directly related to the occupant comfort requirements (OMD7). The decision
in this case was to reuse the class saref:Property that represents qualities of
features of interest that can be measured such as temperature, indoor air quality,
etc. This decision is aligned with the use of saref:UnitOfMeasure (OMD8) to
indicate the units of op:EnvironamentalParameter.
    The model should allow to express if the occupant internal needs are in-
fluencing in a certain way its behavior. The property op:influencedByNeed
connects a behavior to individuals of op:Need. Needs can be further catego-
rized into: a) op:NonPhysicalNeed that gathers all the possible instances that
cannot be quantified like privacy or status; and b) op:PhysicalNeed that rep-
resents comfort requirements that could be expressed by fixed intervals over
environmental parameter values. The property op:definedByRange connects a
need type with the class op:ParameterRange to define a customized envelop.
The op:ParameterRange limits are defined by the attributes op:minRangeValue
and op:maxRangeValue. The range of values are related to a environmental prop-
erty through the n-ary alike class op:EnvironmentalParameter. The physical




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      Fig. 3: Final Conceptualization of the Occupancy Profile Domain




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needs can be classified into op:AccousticNeed, op:IAQNeed, op:VisualNeed,
and op:ThermalNeed.
    In addition, occupant movements (op:Movement) can have an impact over
building energy performance. In obXML, the movement models are specified
by space occupancy specifications and event specifications, gathered in the ini-
tial conceptualization under the class op:MovementSpecification (OMD9).
In the final model, movements are further classified according to whether they
represent random movements inside spaces (op:RandomMovement), or transi-
tions between spaces (op:StatusTransition). The randomness of transition
events can be approximated by stochastic models (indicated by the property
op:specifiedBy) represented by the op:MovementModel concept, which gathers
probabilistic methods as the op:MarkovChainModel. Even though, the obXML
implementation uses attributes related to event duration under probabilistic
models, we consider them as general information that can be attached directly
to a transition event; it means the op:MovementSpecification concept is not
longer needed in the current model.
    A behavior could also be triggered by external factors, like the day of the
week, environmental properties or the room itself, which are modelled by the
concept op:Driver. Although, time can be a driver by itself, it also can be com-
bined with other driver types to indicate when they happen. Taking this double
facet into account we need to introduce the class op:DriverSet, which allows to
combine multiples drivers (op:Driver). Furthermore, the concept of time can be
expressed in many forms in the context of occupancy behavior (OMD10). We
could refer to seasons, days of the week or to specific parts of the day. Because we
need such diversity in the description of time, we look for terms in the well known
Time ontology that could useful for our representation. From that analysis, we
conclude that the concept time:DayOfWeek covers the need for pointing to spe-
cific days of the week and their combinations (weekends, weekdays, etc), that is,
specifying “weekend” would be done by 2 triples, one pointing to Saturday and
other to Sunday with the property op:hasDayOfWeek. This modelling decision
has been taken also for the “all” instances in op:Season and op:TimeOfDay.
The holidays are represented with the attribute op:onHolidays to point to the
specific days of the calendar. Finally, the modelling of op:Meeting (OMD11)
and their schedule has been simplified by considering meetings themselves as
scheduled events that have duration, start and ending time.
    As a final step in the implementation, we evaluated the ontology using
OOPS!. The set of problems detected were categorized into minor and impor-
tant issues. The type of errors that fell into the ”minor” category were related
to missing term descriptions and lack of inverse relationships. According to the
OOPS! nomenclature, minor problems are not real problems but can make the
ontology more appealing to the final user, therefore, we decide to include de-
scriptions for all the terms. The inverse relations were left for future versions of
the ontology, with the idea of not increasing the complexity of the already big
model. The set of problems within the ”important” section indicated the lack
of domain and range definitions in most of the properties. Though this type of




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error is not critical for the ontology’s functionality, we decided to include domain
and range only on those properties that do not interfere with their definitions.


4.3      Publication and Maintenance of the OP Ontology

For the ontology publication, we followed W3C best practices, setting up con-
tent negotiation mechanisms for the OP ontology URI https: // bimerr. iot.
linkeddata. es/ def/ occupancy-profile . From the URI, the ontology can be
retrieved in several RDF serializations, and in a human oriented HTML version
generated with Widoco10 , where diagrams, descriptions and an example are in-
cluded.
    In order to keep track of new requirements or updates related to the ontology,
we use the GitHub Issues section of the OP ontology repository.11 All the issues
requested through the platform will be analyzed by the ontology engineers and
domain experts, leading to a new version of the ontology when needed.


5       Occupancy profile ontology in practice

This section shows an example of how to instantiate the OP ontology based on
a test case provided with the obXML schema. The prefix “data” is used as the
namespace to represent the instances in this example. It is important to mention
that the graph representation of the example (Figure 4) has been simplified to
improve the readability of the diagram. The complete diagram, the RDF code
and the XML example are available at the OP ontology GitHub repository.
    In the example, there is a building (data:Building 1) that con-
tains an office (data:S2 Researcher Office) shared by two researchers
(data:OC Researcher 1 and data:OC Researcher 2). The first occupant
data:OC Researcher 1, a 21 years old male, has a behavior data:B Therm that
predisposes him to set the room thermostat (data:Thermostat 1) to a desired
value. This action is represented by the instance data:Interaction 1 of type
op:SetToControlValue, an its probability of occurrence is described formally by
the instance data:Weibull1DFormula 1. This formula depends on the environ-
mental parameter data:EnvironmentParameter 1 that describes the property
op:Temperature. This behavior is driven by external factors grouped and rep-
resented by the instance data:DriverSet 1 that, in this case, is just conformed
by the environment driver op:Environment 1.
    Apart from punctual interactions with systems, the model is also able
to represent occupant movements inside buildings. The second occupant
data:OC Researcher 2, has the behavior data:B M Researcher which leads him
to stay in his own office 70% of the time. This occupancy activity is represented
by the instance data:SpaceOccupancy 1. Furthermore, the occupant also per-
forms several transitions between spaces during his stay at the office. The first
10
     https://github.com/dgarijo/Widoco/
11
     https://github.com/oeg-upm/bimerr-occupant-behavior/issues




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            Fig. 4: Example of how to instantiate the OP ontology




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transition data:StatusTransition 1 corresponds to his arrival (op:Arrival)
at the installations. This transition can be approximated by a custom model
represented by data:CustomProbabilityModel 1 which states the possible time
when this transition can happen and the probability of occurrence, which in this
case states that at 09:00 am the probability of arrival is 70%. This occupant also
interacts with the systems inside his office, where the instantiating process would
be the same as before. However, in this case, his behavior is also influenced by
thermal comfort needs represented by data:ThermalNeed 1 where the instance
data:ParameterRange 1 declares what are the maximum and minimum comfort
values over the op:Temperature property.


6      Related work

One of the existing resources related to occupancy behaviour is the SimModel,
a data model expressed in the form of an XSD schema that combines building
data (IFC schema) with energy related information (EnergyPlus schema). To
accommodate the data needs from EnergyPlus tools, occupant behavioral data
is encapsulated within the energy information. A transformation service was built
to automatically convert a SimModel XSD schema into their OWL counterpart
[7]. Even though the model is represented in OWL, the concepts and properties
defined are tool-specific, not being able to be reused by other energy estimation
software, lacking the interoperability aimed by this kind of technologies.
     Regarding non-ontological resources about occupancy behaviour, one of the
most interesting endeavors comes from the Annex 66 project. It aimed at provid-
ing a scientific description and clear understanding of energy related occupant
behaviours inside buildings, along with a set of research methodologies and sim-
ulation tools to bridge the gap between occupant behaviour and the built envi-
ronment. This work has been materialized in the DNAS (Drivers, Needs,Actions
and Systems) framework [6] and an XML implementation of the framework [5].
However, up to the authors’ knowledge, no OWL ontology that represents this
model is available. For this reason, in this paper the obXML schema has been
taken as the main non-ontological input to generate the OP ontology in a format
compatible with linked data and semantic web technologies.


7      Conclusions and future steps

This paper has presented the process of developing a semantic model, imple-
mented as an OWL ontology, based on the obXML standard. The ontology is
available online together with human-readable documentation and an example
of use. Along the process it has been observed that different modelling decisions
sometimes are taken for similar problems, for example, whether to reduce the
number of triples when generating data or not, or whether to create a class hi-
erarchy or a SKOS schema for modelling types. This work presents a catalogue
of 10 well-argued decisions that could serve for other ontology developments.




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   Main future lines of work are to extend the ontology evaluation techniques
used, for example including test verification and the elaboration of additional
examples. Authors will also explore the construction of mapping rules in or-
der to transform obXML data into RDF statements automatically. Finally, the
connection of the OP ontology with other domains from the BIMERR network
needs to be evaluated in order to address overlaps, and to determine how this
complementary data (sensor data, building data, etc) can enrich the description
and help in the understanding of occupancy profile information.


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