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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>Raghava Mutharaju[</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>An Ontology Design Pattern for Modeling Pollution?</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>Knowledgeable Computing and Reasoning (KRaCR) Lab, IIIT-Delhi</institution>
          ,
          <addr-line>New Delhi</addr-line>
          ,
          <country country="IN">India</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>0000</year>
      </pub-date>
      <volume>0003</volume>
      <abstract>
        <p>Pollution has been identi ed as a signi cant risk to global ecosystems and living beings. However, the information about pollution is fragmented and there is no meaningful organization of information despite several ongoing e orts to monitor it. Organizing the information about the pollution, such as the pollutants, their observations at di erent spatio-temporal points and the carriers in the form of an ontology will be very helpful to the applications that work with the different heterogeneous pollution data sources. We propose an ontology design pattern (ODP) for pollution that captures its general characteristics and can be used as a building block for modeling speci c categories of pollution such as air, water and soil. The Pollution ODP is available on the ODP portal at http://ontologydesignpatterns.org/wiki/ Submissions:Pollution. It is also available for public comments at https://github.com/kracr/aq-structured-platform/blob/main/On tology/PollutionODP/PollutionODP.owl with an Apache License 2.0.</p>
      </abstract>
      <kwd-group>
        <kwd>Pollution</kwd>
        <kwd>Ontology Design Pattern</kwd>
        <kwd>Pollutants</kwd>
        <kwd>Air Pollution</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        The introduction of substances into the environment that are harmful to the
living organisms is de ned as pollution [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. These harmful substances can be solids,
liquids, or gases produced in higher than usual concentrations. These substances
are referred to as pollutants. Pollution could a ect many natural resources, such
as the air, water sources and soil. The need to study these pollution types is of
utmost importance. Air pollution is regarded as a global health emergency and
the e ect of bad air quality is deadly. It leads to asthma, other respiratory
illnesses and heart disease. Air pollution is responsible for more deaths than many
other risk factors, including malnutrition, alcohol use and physical inactivity [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ].
Similarly, there is a pressing need to study water and soil pollution [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Di erent
? Copyright © 2021 for this paper by its authors. Use permitted under Creative
      </p>
      <p>
        Commons License Attribution 4.0 International (CC BY 4.0).
heterogeneous data sources are made use of to build pollution monitoring
applications [
        <xref ref-type="bibr" rid="ref2 ref3">2,3</xref>
        ]. An ontology design pattern(ODP) [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] that captures the abstract
details of the pollution will be bene cial to these applications.
2
      </p>
    </sec>
    <sec id="sec-2">
      <title>Related Work</title>
      <p>
        Attempts to model pollution have focused on air pollution, probably because of
the readily available data of pollutant concentrations. Claudine et al. [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] built
an air quality ontology and used that along with the 3D models of a city. The
ontology proposed in [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ] links air pollutants with meteorological factors. EnvO1
is a very broad ontology that describes the environment by focusing on biomes.
Dalia et al. [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] built an air pollution ontology by focusing on species, sensors,
pollutants and meteorological factors. They have designed one ontology for each
of these factors. We studied these ontologies along with several data sources such
as pollutant concentration2, weather data3 and wind trajectory4 to design the
Pollution ODP. We also capture the spatio-temporal aspect of pollution in the
ODP, which has not been considered in some of the pollution ontologies. The
Pollution ODP has been annotated to indicate the ODPs that were used and
submitted for a review on the ODP community portal5.
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>Pollution ODP Description</title>
      <p>
        The pollution ODP makes use of the trajectory ODP [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ], observation ODP [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]
and the stub meta-pattern [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. We use cpannotationschema6 to describe the
intent, scenarios, consequences and components of the ODP. The schema of the
pollution ODP is given in Figure 1. We describe the concepts and the properties
of the pollution ODP in the subsequent sections.
3.1
      </p>
      <sec id="sec-3-1">
        <title>Concepts</title>
        <p>{ Pollution. It is the core concept in the ODP to represent pollution and is
linked to the contributors of pollution. Some of the instances of Pollution
could be air pollution, water pollution, soil pollution, space pollution, and
sound pollution.
{ Observation. The Observation concept is modeled from the Observation
ODP. It represents a spatio-temporal observation. We use it to capture the
concentration and prescribed standards for a particular pollutant. With
respect to the Observation ODP, Pollutant and
PrescribedStandardForPollutant is the situation and TimeEntity, PlaceEntity are the parameters
of the observation.</p>
        <sec id="sec-3-1-1">
          <title>1 http://environmentontology.org/</title>
          <p>
            2 https://cpcb.nic.in/
3 https://weatherstack.com/
4 https://www.ready.noaa.gov/HYSPLIT disp.php
5 http://ontologydesignpatterns.org/wiki/Main Page
6 http://www.ontologydesignpatterns.org/schemas/cpannotationschema.owl
{ DirectContributor. The DirectContributor concept represents the
contributors that directly a ect the pollution. Pollutant is a subclass of
DirectContributor. Some examples of pollutants include biological pollutants (viruses,
pathogens, bacteria, etc.), chemical pollutants (toxic metal, radionuclides,
organophosphorus compounds, gases, etc.) and physical pollutants (sound,
thermal energy, space debris, etc.) present in a particular environment.
{ IndirectContributor. The IndirectContributor concept represents
concepts that indirectly contribute to the pollution at a particular spatio-temporal
point. These include environmental factors like temperature, the air or water
streams owing into or out of a particular place, the socio-economic factors
such as policies and demographics. We have modeled only the Carrier
concept as the subclass of IndirectContributor since other indirect
contributors are speci c to certain kinds of pollution.
{ PlaceEntity and TimeEntity. These concepts denote the place and time
for a spatio-temporal observation. They are linked to the Observation and
TrajectoryPoint concepts by the atPlace and atTime properties.
{ PrescribedStandardForPollutants. This is a stub meta-pattern [
            <xref ref-type="bibr" rid="ref10">10</xref>
            ] that
can be used to describe the prescribed ranges for pollutants. For a
particular location, pollutants have a de ned range of permissible concentrations
that are speci ed by the various global authorities7. A standard for a
pollutant may change with time and place. Hence the
PrescribedStandardForPollutants concept is linked to the Observation concept by the
hasObservation property.
7 2005 WHO guidelines prescribe the range for air pollutants such as particulate
matter (PM), ozone (O3), nitrogen dioxide (NO2), etc., available at http://whqlibdo
c.who.int/hq/2006/WHO SDE PHE OEH 06.02 eng.pdf?ua=1.
{ Carrier. This concept is a subclass of the IndirectContributor concept
and represents the air, water, or other kinds of streams owing into or out
of a particular place. It is linked to the Trajectory concept through the
hasTrajectory property. Carriers are generally observed to a ect the
concentration of pollutants at a particular place and are important in modeling
pollutants. To represent the pollutants that might be carried through a
trajectory, the Carrier concept is linked to the Pollutant concept by the
carriesPollutant property. To specify the location of the source of
pollutants in a carrier trajectory, nearby property can be used. This links the
pollutant sources such as factories in the case of wind stream carrier or drains
in the case of water stream carrier to the TrajectoryPoint. The
applications that have such a requirement can make use of the nearby property,
but we excluded it from the ODP because it is not su ciently general.
{ Trajectory. The Trajectory concept represents a set of ordered
spatiotemporal points and has been directly adopted from [
            <xref ref-type="bibr" rid="ref9">9</xref>
            ]. It is linked to the
TrajectoryPoint and TrajectorySegment through the hasPoint and
hasSegment properties. The nextPoint property links trajectory points in the
appropriate order within a trajectory. The segments in the trajectory are
de ned by a starting trajectory point fxi; yi; tig and an ending trajectory
point fxj; yj; tjg where ti, tj denote time points such that ti &lt; tj. The
TrajectorySegment concept represents this notion of a segment which is
connected to two xes through startsFrom and endsAt properties.
3.2
          </p>
        </sec>
      </sec>
      <sec id="sec-3-2">
        <title>Properties</title>
        <p>{ atPlace, atTime. They connect Observation and TrajectoryPoint
concepts to the PlaceEntity and TimeEntity respectively. Since an instance
of Observation or TrajectoryPoint can be associated with at most one
timestamp, the atPlace and atTime properties are functional.
{ startsFrom, endsAt. These functional properties connect a
TrajectorySegment to starting and ending TrajectoryPoint representing the starting
and ending point of a segment.
{ carriesPollutant. This property represents the pollutants that a Carrier
can carry. It connects Carrier to the Pollutant concept and represents
the pollutants being carried away by a carrier. The trajectory of the carrier
dictates the displacement of pollutants.
{ hasTrajectory. This property connects the Carrier concept to the Trajectory.
{ hasContributor. This property connects the Pollution concept to the</p>
        <p>Contributor concept.
{ hasPoint. This property connects the Trajectory with the TrajectoryPoint.
{ hasPrescribedStandards. This property connects the Pollutant concept
to the stub PrescribedStandardForPollutant concept.
{ hasObservation. This property connects Pollutant and
PrescribedStandardForPollutant concept to the Observation concept. It can be used to
capture the concentration of pollutants or a prescribed standard for a
particular pollutant with the TimeEntity and PlaceEntity as the parameters
of the observation.
{ hasSegment. This property connects the Trajectory to the
Trajectory</p>
        <p>Segment.
{ nextPoint. This property links each point represented by the TrajectoryPoint
to the next point forming a chain of ordered points.
3.3</p>
      </sec>
      <sec id="sec-3-3">
        <title>Axioms of the Pollution ODP</title>
        <p>The axioms that are part of the Pollution ODP are discussed here.</p>
        <p>Carrier v 8carriesPollutant:Pollutant</p>
        <p>Carrier v 9hasTrajectory:Trajectory
Pollution v 9hasContributor:Contributor</p>
        <p>Observation v 9atPlace:PlaceEntity</p>
        <p>Observation v 9atTime:TimeEntity</p>
        <p>TrajectoryPoint v 9hasPoint :Trajectory
Trajectory v 9hasSegment:TrajectorySegment
hasSegment startsFrom v hasPoint
hasSegment endsAt v hasPoint
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)</p>
        <p>Axioms 6, 7, 8 and 9 capture the relation between the Trajectory,
TrajectoryPoint and the TrajectorySegment concepts.
3.4</p>
      </sec>
      <sec id="sec-3-4">
        <title>Competency Questions</title>
        <p>The Pollution ODP answers the following competency questions.
1. What are the contributors of the pollution?
2. What is the pollutant concentration at a particular time and place?
3. What are the carriers that contributed to the pollution?
4. What are the pollutants carried by a carrier?
5. What are the prescribed standards for a particular pollutant?
6. What is the trajectory of a carrier for a pollutant?
4</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Use Cases</title>
      <p>The Pollution ODP can be used as a building block to model various
pollution types such as air, water and soil. They can be added as subclasses of the
Pollution concept. An example use case of air pollution can describe the
concentration of pollutants in the air at a particular spatio-temporal point through
the Observation and Pollutant concepts. Similarly, the pollutants carried by
the air stream can be captured by the Carrier concept. The Weather concept
can be added as a subclass of IndirectContributor concept in the concrete
implementation of this ODP to represent the weather related factors that
contribute to air pollution. These concepts can be extrapolated to water, soil and
other types of pollution as well.</p>
    </sec>
    <sec id="sec-5">
      <title>Conclusion and Future Work</title>
      <p>Pollution exists in many forms in the environment and a ects individuals as
well as ecosystems. An ontology design pattern for modeling various sources and
characteristics of pollution can be used e ectively as a building block by multiple
applications that work with pollution data. We introduce an ODP for modeling
pollution and discuss its competency questions, concepts and properties. We also
describe some use cases of the ODP. The ODP and its documentation are publicly
available at http://ontologydesignpatterns.org/wiki/Submissions:
Pollution and at https://github.com/kracr/aq-structured-platform/bl
ob/main/Ontology/PollutionODP/PollutionODP.owl with an Apache License
2.0.</p>
      <p>
        We plan to use the Pollution ODP to model air pollution by considering
the pollutant concentration, weather and wind trajectory data sources. The air
pollution ontology will be populated using these data sources by converting the
semi-structured data (csv, json, etc.) into an RDF8 graph using YARRRML [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ].
      </p>
      <p>Acknowledgements. This work is partially supported by the Infosys Center
for Arti cial Intelligence (CAI) at IIIT-Delhi, India.</p>
      <sec id="sec-5-1">
        <title>8 https://www.w3.org/TR/rdf11-primer/</title>
      </sec>
    </sec>
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