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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Cultural Mapping of Villages in India Using CIDOC-CRM</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Toshant Sharma</string-name>
          <email>sharma.toshant@research.iiiit.ac.in</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Navjyoti Singh</string-name>
          <email>navjyoti@iiit.ac.in</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>International Institute of Information Technology Hyderabad</institution>
          ,
          <country country="IN">India</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>ion over the CIDOC CRM (ISO 21127:2014) ontology for the purpose of the cultural mapping of villages of India and discuss with case studies how cultural information in context of Indian villages can be captured, preserved and new relationships between cultural entities visualized using this ontology.</p>
      </abstract>
      <kwd-group>
        <kwd>Ontology</kwd>
        <kwd>Cultural Mapping</kwd>
        <kwd>RDF Triples</kwd>
        <kwd>CIDOC-CRM</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        In the domain of cultural mapping [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] the captured information, scattered over
a large set of in-coherent sources (government publications, databases, web sites,
surveys etc.) in di erent formats and can be accessed only in a fragmented
manner as the interconnections between data sets are scanty. In the context of Indian
Cultural Heritage, heterogeneity is one of the main characteristics and ontologies
o er solutions to the semantic heterogeneity problem [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Using ontology in
integration architecture as a global schema to which metadata from di erent sources
can be mapped provides a new approach by which diverse cultural network
semantics can be described independently of cultural data source characteristics
and in turn provide a conceptual schema allowing cultural data exchange among
heterogeneous information systems and users. With 68.84% people residing in
villages having long standing oral-traditions and non-existence of external
retention systems through ages, there is need to externalize both tangible and
intangible aspects of cultural heritage of di erent communities. Therefore, in
order to `map' Indian culture it becomes imperative to capture the cultural
dynamics operating at the granularity of constituent villages.
      </p>
      <p>
        We propose an abstraction over CIDOC CRM [
        <xref ref-type="bibr" rid="ref11 ref15 ref9">9,11,15</xref>
        ] ontology for cultural
mapping of the Indian villages. CIDOC CRM is a core generic ontology and ISO
standard (ISO 21127) for the semantic integration of cultural information with
library, archive and other information [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] but lacks domain speci c specializations
to better capture, represent di erent cultural contexts. Acting as the underlying
framework, time and again both abstractions and extensions are made to the
model [
        <xref ref-type="bibr" rid="ref6 ref8">6,8</xref>
        ] for knowledge representation in di erent contexts and sub-domains
of cultural heritage. The paper makes the following contributions
describing an abstraction over CIDOC CRM for specialized purpose of
cultural mapping in the context of Indian villages
providing examples of how information can be modeled with this model
describing an implementation of the proposed ontology
2
      </p>
    </sec>
    <sec id="sec-2">
      <title>Related</title>
    </sec>
    <sec id="sec-3">
      <title>Work</title>
      <p>
        Doer [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] gives an overview of domain of cultural heritage, schema integration
problem in cultural heritage, characteristics of cultural ontologies and reviews
CIDOC-CRM, FRBRoo and other core ontologies in the domain. Stephan [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ],
Crofts et al.[
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] describe the de nition, structure and pertinence of CIDOC-CRM.
Lieto et al.[
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] propose to adopt and extend the CIDOC-CRM to describe some
of the traits of the contemporary artworks by discussing three examples of an art
installation in a museum, a live performance and, a physical modern artwork.
The qualitative aspect of addition of `score' as subclass of `Design and
procedure' is discussed and the class is proposed as an extension. Tan et al.[
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] give
representation of \Funeral Dance" based on CIDOC-CRM, wherein a domain
ontology is created for the domain of funeral dance by modeling the domain in
Protege using CIDOC-CRM as the base model. Hu et al.[
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] apply the CIDOC
Conceptual Reference Model to the construction of the entities and properties
of the knowledge ontology of the Pang Wang Festival.
      </p>
      <p>
        An extension of CIDOC-CRM, for the Invisibilia project, is given by Ng et
al.[
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] where the notion of performance is proposed for the integration into the
ontology. Emphasizing that more specialized vocabularies are necessary, classes of
performance activity, performance procedure, instrument, equipment and digital
object are proposed for digital preservation purpose of interactive multimedia
performances. Theodoridou et al.[
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] propose an extension of CIDOC-CRM aimed
at modeling the notion of reliability and provenance. By introducing four new
specializations of material and immaterial items and six new specializations of
events, the proposed extension is used to capture the modeling and the query
requirements regarding the provenance of digital objects.
      </p>
      <p>
        Hernandez et al.[
        <xref ref-type="bibr" rid="ref13">13</xref>
        ] describe the initiative for the construction of an
ontology that compiles the knowledge around the cultural heritage related to region
of Cantabria in Spain by converting unstructured high-quality information
prepared by subject matter experts to semantic form employing RDF schema of
existing ontologies.
3
      </p>
    </sec>
    <sec id="sec-4">
      <title>Ontology Construction Methodology</title>
      <p>
        The methodology involves ontology modularization of the domain and then
iterative modeling through example representation. We rst modularize the large
domain of cultural mapping in context of Indian villages into small ontologies.
To create modularized ontologies we use a normalization approach as proposed
by Alan Rector [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. In this approach each ontology is decomposed into disjoint
skeleton taxonomies, which are restricted to simple graphs. These skeleton
taxonomies are then integrated with CIDOC CRM, which acts as a common base
to which di erent small branch ontologies are added. The changes to the model
generated by mapping and adding skeleton ontologies to CIDOC are made using
iterative example modeling in terms of the intermediate ontologies. Continuous
ontology evolution form the basis for our iterative ontology modeling approach.
Figure 1 depicts the steps carried out, ontology is available publicly at [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ].
      </p>
      <p>Update skeleton Ontology. Based on the example representation in ontology
update the skeleton ontology adding classes and properties minimally as
necessary and possibly restructuring the class hierarchy to better re ect the
knowledge.</p>
      <p>Integration with CIDOC-CRM. The next step is to integrate the smaller
skeleton ontologies with the common base ontology i.e. CIDOC. The
consistency and correctness of the model is to ensured i.e. disjoint classes can't
have common individuals, the properties must exist between the entities
which lie in their de ned domains and ranges.</p>
      <p>Veri cation. The nal step is veri cation that the applied changes actually
implement what was desired. If the resulting ontology is not satisfactory
or contains inconsistencies new changes are implemented into the skeleton
ontologies and the process is repeated.
4</p>
    </sec>
    <sec id="sec-5">
      <title>Extension Description</title>
      <p>4.1</p>
      <sec id="sec-5-1">
        <title>Performative Culture</title>
        <p>
          The class performative culture is proposed as an abstraction to encapture the
intangible aspects of culture, having spactio-temporal projections that can be
expressed through medium of live performance for example music, dance,
theatre. As an specialization (subclass) of the class propositional object (E89), this
class is limited to cultural entities that have a changing extension in time or
in other words have a performance stretched in time associated with them for
example individuals belonging to music, theatre, rituals and dance. Figure 2
shows the schema for the class. In order to represent location associated with
propositional object using CIDOC-CRM, rst an event associated with an
individual of that propositional object class is represented and that is linked to
a location. Another way of representation is using P67 (refers to) but this does
not capture the semantics fully for a statement of form \individual X of
performative culture is local to locations l1 and l2". We capture this process through
association of location with individual of class performance so as to prevent the
loss of information.
4
A relevant extension of cidoc-crm for capturing the performative aspects of the
intangible cultural heritage is given by Ng et al.[
          <xref ref-type="bibr" rid="ref5">5</xref>
          ] where the notion of
performance is proposed for the preservation of multimedia performances. As Lieto et
al.[
          <xref ref-type="bibr" rid="ref12">12</xref>
          ] point out, a limitation of this contribution, however, is given by the fact
that this extension is limited to the exclusive introduction of the class
Performance in the ontology, without any speci cation about the relation that such
type of class (and therefore the members of such class) entertain with the other
ontological components (actors, roles, processes etc).
        </p>
        <p>The performance class proposed by Ng et al. primarily aims at preservation
rather than description of the interactive multimedia performance and lacks
relationships to capture the cultural dynamics like motivation and context for
performance, historical and literature references in performance active in the
performance. We propose class Performance as a temporal construct and a
specialization (subclass) of class E7 (activity), the schema is shown in gure 3. Here
an object of performative culture motivates(P17) a performance which has
associated actors, location and appellation. The performance can also be represented
by digital object(P129).
4.3</p>
      </sec>
      <sec id="sec-5-2">
        <title>Tangible Cultural Object</title>
        <p>In order to capture the legacy of physical artifacts and aesthetic, historic, or
social value associated with them a specialization of E22 (man made object)
is proposed. This class comprises tangible cultural entities i.e. physical objects
with real boundaries purposely created by human endeavor. The individuals of
this class include cultural objects both moveable and stationary like paintings,
cuisine, clothing, monuments etc. The individuals of class tangible cultural
object(TCO) have associated individuals of E39 actors in the contexts of both
producer of the cultural object and owner. P105 directly represents the actor
holding the rights to the TCO. Property P108 connects TCO to the event
production (subclass of E5 Event), P14 further describes the actor who carried out
the production event of the TCO. The production event also has an associated
time span with it.
4.4</p>
      </sec>
      <sec id="sec-5-3">
        <title>Survey</title>
        <p>
          The class survey, encompasses not only the statistical studies of the size,
structure, distribution of populations along with spatial or temporal changes in them
but also represents the general methodologies to collect data about di erent
tangible and intangible cultural aspects of an individual village. The class survey is
described as a subclass of Design and Procedure. The property P106 links the
individuals of class survey to its constituent documents(E31), design and
procedures(E29) as individuals of class information objects(E73) which are sub-classes
of symbolic object(E90).
We borrow the specialization `digital object' of class E73 from Theodoridou et
al [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ].
        </p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>Case Studies</title>
      <sec id="sec-6-1">
        <title>Importing Census Data</title>
        <p>
          Here we show a case study of importing and representing the demographic census
data (Census of India 2001) using the proposed extension. The census of India
2001 contains 55 social, cultural and economic attributes in a relational table all
having numerical values for around 628,000 villages of India. Figure 6 shows the
schema used to represent the data using the model. To import the census data
available in relational form into the ontology, we use Domain Semantics-driven
Mapping Generation methodology [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ] wherein the mappings are generated from
RDB to RDF by incorporating domain semantics that are often implicit or not
captured at all in the RDB schema. The census is de ned as an individual of
class survey, linked by P94 to a creation activity that has associated time span
and individual. A set of sub properties of Data property PDN1 is de ned to
add census data to individuals of class village. Treating a speci c village as
an individual the attributes from census data are mapped to data properties
of the entity village (sub properties of data property PDN1). Each attribute
(total 55 of such attributes) de ned in the census relational table having an
associated numeric value is mapped correspondingly to a data property. The
attribute values are stored as the literal values of the data property.
        </p>
        <p>
          The schema is de ned in Jena [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ], to import and store the census data
into the model we use RDF(resource description framework). The census data
is rst pre-processed from CSV (comma separated values) text to JSON format.
Using this format the villages are rst organized into a hierarchical tree like
structure with state, district, sub-district and village at di erent levels. While
transforming into RDF form this hierarchy is maintained by use of the property
P89(contains). Treating a village as subject of a resource the attributes from
census data are mapped to properties in RDF format where each attribute
dened in the table is mapped correspondingly to a data property. The attribute
values are stored as the literal values of the property. The total number of triples
added for the state of Punjab having 25,678 villages are 1,437,968. Refer [
          <xref ref-type="bibr" rid="ref19">19</xref>
          ] for
detailed explanation.
5.2
        </p>
      </sec>
      <sec id="sec-6-2">
        <title>Case Study of Ramlila Theatre</title>
        <p>Ramlila is a theatrical performance based on the epic Ramayana. Ramlila
consists of a series of scenes that include song, narration, recital and dialogue. A
semantic graph is constructed for the folk drama of Ramlila wherein the
ontological model captures the relationships between di erent entities and describe
knowledge regarding Ramlila. Figure 7 describes concepts of the theatrical form
of ramlila captured using the proposed model.
5.3</p>
      </sec>
      <sec id="sec-6-3">
        <title>Cultural Semantic Graph of village Preet Nagar</title>
        <p>
          Using the model we attempt to capture the cultural heritage of Preet Nagar
village existing in the Indian state of Punjab. For that purpose, the cultural data
is imported through means of extensive surveying. Figure 8 schema shows how
a single example each from domains of surveys, tangible cultural object,
performative culture are related to the village. The survey questionnaire consists
of four tables to be lled up by takers about number and type of architectural
locations, ethnographic constitution of village, number and type of artists
existing in village and number and type of shops in village. The structure of the
data collection tables had to be designed keeping in mind that the vast amount
of variance in domain listed has to be captured. For each of the survey table
an individual of class survey is declared and the attributes from the relational
table are de ned as the data type properties of the village. The relation of the
village and the survey is represented through property P129 (is subject of). An
example of this methodology would be, in ethnographic survey list all religions
and castes (jatis) and then ask for numeric values of each existing in the village.
However there are more than 3000 castes (jatis) in India [
          <xref ref-type="bibr" rid="ref18">18</xref>
          ], asking
participants taking surveys to ll up huge tables is not practical, rather it is better
to ask for the castes existing in the village only and construct a relational table
for capturing that. The ethnographic survey table for a village had only three
columns (religion, caste, number of households), the participants list the data
accordingly.
        </p>
        <p>
          The tables are converted into RDF triples and imported into the ontology.
To convert a table into equivalent RDF form we use blank nodes. A blank node
(also called bnode) is a node in an RDF graph representing a resource for which
a URI or literal is not given and can be used to describe multi-component
resources [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ]. The attributes stored in the table are mapped to predicates of blank
nodes in RDF ending the chain at a literal value. The path from the village to
the literal value describes what the literal value is representing. The process is
straightforward and is illustrated in gure 9 which shows a section of the table of
ethnographic decomposition and its corresponding model. The URI associated
with village is appended by the predicates to generate URIs depicting di erent
ethnographic groups in the village. Using the same methodology for conversion
from survey tables to RDF form, we generate RDF triples for tables of type and
number of artists, type and number of architectural sites, number and type of
shops in the village Preet Nagar.
6
        </p>
      </sec>
    </sec>
    <sec id="sec-7">
      <title>Conclusions And Future Work</title>
      <p>One of the advantages of using RDF that has been stressed throughout is the
way two separate graphs are automatically linked if they share as much as a
single common resource node, which can provide insights into how di erent agents
operating in a diverse and vivid cultures interact and manifest themselves.
Relying upon expression of history as a series of events with associated time periods
and above mentioned process of extracting relations from descriptive texts, a
methodology and a use case for constructing a semantic graph of the history of
villages are implemented as a prototype. This is yet to be developed further and
not hence discussed here. Future works include improved cultural data collection
and curation of collected content through the medium of a crowd sourcing web
application focused on both surveys and textual descriptions. Further testing,
specializations and example modeling, case studies using the model are open
ended processes for the future.</p>
    </sec>
  </body>
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