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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Bharathi-An Applied Semantic Intelligence Use Case for Public Data in India</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Asha Subramanian</string-name>
          <email>asha@semanticwebindia.com</email>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Manikanta Vikkurthi</string-name>
          <email>manikanta@semanticwebindia.com</email>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Gunjan Pattnayak</string-name>
          <email>gunjan@semanticwebindia.com</email>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Akshay K S</string-name>
          <email>akshay@semanticwebindia.com</email>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Harika Vikkurthi</string-name>
          <email>harika@semanticwebindia.com</email>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          ,
          <addr-line>Census</addr-line>
          <country country="IN">India</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Semantic Web India</institution>
          ,
          <addr-line>Bangalore, Karnataka</addr-line>
          ,
          <country>India. Home Page:</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Welfare -Union Government, Department of Health and Family Welfare -State Government of Karnataka), sector (e.g. Environment</institution>
          ,
          <addr-line>Health</addr-line>
          ,
          <institution>Education), the administrative region for which the data has been collected (e.g. State -Karnataka, District -Bangalore Urban, City -Bangalore) etc. The metadata is available in un-structured and semistructured formats in various home pages of government of India web sites such as GOI Directory</institution>
        </aff>
      </contrib-group>
      <fpage>486</fpage>
      <lpage>498</lpage>
      <abstract>
        <p>Data sets published for public consumption related to governance typically contain common metadata. This metadata normally describes the publishing organisation, the domain, the administrative region and a topic that the data best describes. A relevant semantic vocabulary will not only facilitate linking the metadata through meaningful contexts but also enable grounding related information from diverse public data sets using semantic entities defining the metadata. In this paper, we present Bharathi -Linked Data Vocabulary for the Indian context. Bharathi contains information regarding government organisations at the union &amp; state government level, administrative regions, sectors, sub sectors and common topics used frequently in the vocabulary of the government functions. Further, Bharathi contains links to other open vocabularies such as GeoNames for geographical locations. The schema of Bharathi uses existing established ontologies making it inter-operable and extensible. We describe Bharathi along with a live use case of its application in accomplishing a semantic Covid19 data analysis for India.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Linked Data</kwd>
        <kwd>Knowledge Graph</kwd>
        <kwd>Ontology</kwd>
        <kwd>Semantic Intelligence</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>discovery of inter-connected relationships sample information from Bharathi.
across these pivotal entities by humans and We start with the canvas of Related Work
machines. In many cases, the same entity (a (Section 2) where we list references to
simgovernment organisation or an administra- ilar work and set the context for our
contive region) is referred by its respective code tribution. Next, we provide an overview of
across diferent web sites making it a humon- Bharathi followed by an introduction to the
gous task to connect the information across Bharathi ontology in Section 4. Section 5
dethe two data sources although they relate to tails the process of generation of Bharathi.
the same entity. Therefore, creating an ap- Real world applications of Bharathi are
prepropriate semantic framework for a knowl- sented in Section 6. We conclude with a brief
edge based representation for this metadata summary and thoughts on future directions
is paramount. Such a semantically enriched in Section 7.
knowledge representation will substantially
help in linking public data sets and also
provide a valuable inter-operable, reproducible 2. Related Work
and machine-readable resource for the
scientific and industrial community. To the best
of our knowledge, no reasonably large and
up-to-date corpus of linked data information
about government entities, their
classifications and their inter relationships specifically
for the Indian context has been made publicly
available yet, in the form of a machine
readable resource. This paper presents a use case
for applied semantic intelligence – Bharathi
and its potential applications.</p>
      <p>
        Bharathi is populated using a
semiautomated pipeline that periodically
harvests data from various government of India
websites, annotating the entities and lifting
the semantics into a RDF6 grounded by a
sound model based on established
vocabularies such as Organisation Ontology7, SKOS
Vocabulary8 and the GeoNames Knowledge
base9. We provide a web interface accessible
at http://semanticwebindia.in/bharathi for
exploring the underlying knowledge graph
of Bharathi, enabling users from outside the
scientific community to find, retrieve and
Several research eforts such as [
        <xref ref-type="bibr" rid="ref1 ref2 ref3 ref4 ref5 ref6 ref7 ref8">1, 2, 3, 4,
5, 6, 7, 8</xref>
        ] have shown interest in linking
public data with semantic metadata to
enable intuitive linking of information from
diverse sources. The research eforts
specifically to model the metadata around public
data can be found in [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] where the authors
presents Gridworks-based data workbench
application to help in converting open
government data to linked data by using
standard Data Catalog Vocabulary. The data
catalogs of open data are an input to the
application, yielding the linked data form. [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]
presents a semantic government vocabulary
to create annotations of open government
data. It details the diferent layers of the
vocabulary depending on diferent ontological
terms found in open government datasets. It
also demonstrates how to use the vocabulary
to annotate open government data at
diferent levels. [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] explores the documentation
needs for open government data with specific
focus on metadata interoperability issues. It
presents two methodologies for
interoperability after studying a variety of open
govthe Registrar General and Census Commissioner, India
      </p>
      <p>
        6Resource Description Framework: https://www. ernment metadata, globally recognized
stanw3.org/RDF/ dards and guidelines. The outcomes of the
7org: http://www.w3.org/ns/org# ifrst approach are juxtaposed with those of
98sgkno: sh:thtptt:p//:w//wwww.wge.won3.aomrge/s2.o0r0g4/02/skos/core# the second in the light of interoperability
during the metadata integration process. [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] metadata specifically for the Indian context
presents a methodology, five basic steps and a to enable a powerful semantic integration of
model to publish statistical data coming from public data related to governance in India.
tabular data sources or relational databases
in the form of linked open data. It follows
the best practices for publishing linked data, 3. Bharathi Overview
a W3C working group note such as
providing URI construction suggestions following Bharathi is populated using data extracted
URI policy rules, reuse of standard vocab- from a number of government of India web
ularies, such as the Data Cube Vocabulary, sites whose content is created and
mainSKOS, etc., converting data to RDF and pro- tained by the National Informatics Centre
viding access to the converted data. [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ] de- (NIC), Ministry of Electronics and
Informascribes the attempt at building “AKTivePSI”- tion Technology, Government of India. In the
an initiative by the Ofice of Public Sector In- current version of Bharathi, we consider
information, UK to adopt semantic web tech- formation from https://lgdirectory.gov.in/13,
nology for large scale integration, sharing goidirectory.nic.in/, http://censusindia.gov.
and reusing the public data for the benefits in/ and https://data.gov.in/ to build the
of government, businesses and citizens alike. knowledge graph for metadata around
adThe key outcome due to the success of this ministrative regions and their codes,
governpilot project led to more increased aware- ment entities and their classification, various
ness amongst the government bodies about sectors and their links within the respective
the power of semantic web technology. government function. While Bharathi is
      </p>
      <p>
        While there is a prolific attempt to intro- extensible in including new sources of
induce a semantic knowledge framework to formation, the extraction pipeline will need
extract and maintain the metadata required modification depending on the structural
for semantic integration of public data in specifications of the source. The output
the western nations, there have been none from the extraction pipeline is converted
such coordinated and specific eforts in In- into semantic entities using the Bharathi
dia to the best of our knowledge. DBpedia ontology (Refer Section 4). The Bharathi
resources (extracted from Wikipedia infor- knowledge graph is currently accessible
mation) do exist for India, though in many from a Virtuoso triplestore with a SPARQL
cases they are not up-to-date with the in- endpoint at http://www.semanticwebindia.
formation published on the Government of in/BharathiLive/sparql. All entities of
India web sites. The motivation to create Bharathi are semantically linked and
accesBharathi stems from extensive research work sible using persistent resolvable identifiers
that accomplished semantic integration of following the W3C best practices. Bharathi
open data tables published in data.gov.in us- is released under a Creative Commons
ing entities from Linked Open Data (LOD)10 Attribution-ShareAlike 4.0 International
namely DBpedia11 and Wikidata12 [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ], [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. License14. The web interface is accessible at
Bharathi is our contribution to create, main- http://www.semanticwebindia.in/bharathi/
tain and sustain this knowledge graph of allowing users to search and browse
10LOD: https://lod-cloud.net/ 13https://lgdirectory.gov.in/ : LOCAL
GOVERN11DBpedia: https://wiki.dbpedia.org/ MENT DIRECTORY – Complete directory of land
re12Wikidata: https://www.wikidata.org/wiki/ gions/revenue, rural and urban local governments
Wikidata:Main_Page 14https://creativecommons.org/licenses/by-sa/4.0/
Bharathi. The knowledge graph is up- tion of established vocabularies was made to
dated every 3 - 6 months, depending on ensure 1) interoperability of the knowledge
the changes to the information at source. base through reuse 2) adherence to global
Information related to the knowledge graph definitions of schema for known entities by
dumps and ontology metrics can be accessed reusing terms and most importantly 3)
leverat http://semanticwebindia.in/bharathi/ aging of community support for linked open
BharathiKG. data cloud vocabularies.
      </p>
      <p>The core element of Bharathi
ontology is the Organisation class
4. Bharathi Ontology (bhorg:Organisation16) derived as a subClass
of org:organization. This entity is used to
The underlying schema for Bharathi uses es- denote any public, private or government
tablished ontologies and vocabularies such organsiation in India. The other core
eleas the Organisation ontology and the SKOS ment of the Bharathi ontology is the use
vocabulary to define the building blocks for of skos:Concept to represent the
classificathe metadata pertaining to government or- tion hierarchy to denote one of the three
ganisations, administrative regions, gover- classifications namely –an organisation
nance sectors and the classification hierar- classification, a governance sector or a topic
chy linking these entities. Figure 1 illustrates within a sector. Separate Concept Schemes
the domain model for the Bharathi ontol- (skos:ConceptScheme) have been defined to
ogy. The Bharathi ontology with name prefix distinguish between these three diferent
bhorg15 contains the base classes and proper- types of classifications. Each concept scheme
ties used by the knowledge graph. The selec- has its own hierarchy starting from a Top
15bhorg: http://semanticwebindia.in/bharathi/ont/
org/
16bhorg:Organisation - http://semanticwebindia.in/
bharathi/ont/org/Organisation
Concept (skos:hasTopConcept). An instance
of type bhorg:Organisation has the following
object properties 1) org:hasSubOrganization
–inherited from the org:Organization class
and used to link sub organisations 2)
org:subOrganizationOf –inherited from the
org:Organization class and used to link
to the parent organisation 3) org:linkedTo
–inherited from the org:Organization class
and used to link related organisations and
4) bhorg:hasSpatial –property defined in
the extended class to link to the GeoNames
Feature (gn:Feature) associated with the
instance. The bhorg:Organisation entity also
has data properties to associate the names
(primary and alternate), URL, abbreviations
and codes with the organisation. All the
extended classes and properties of the Bharathi
ontology have been provided with detailed
annotations in line with RDF principles.</p>
      <p>Refer Figure 1, the oval objects represent
entities and the corresponding rectangular
entities linked by rdf:type (a) labelled link
(black dashed link in the figure) indicate the
respective instances. All government
organisations and administrative regions are
instances of the bhorg:Organisation entity
while organisation classifications,
governance sectors and their hierarchical
structures are defined using the SKOS ontology.</p>
      <p>As illustrated in Figure 1, “Science and
Technology Department West Bengal” is a
government entity having classification “State
Department” and is a sub organisation in
the “State” of “West Bengal”. The
administrative region “West Bengal” is linked to a
GeoNames Feature using the corresponding
GeoNames knowledge base. While the SKOS
concepts “State” and “State Department”
belong to the concept scheme “Organisation
Classification”, the SKOS concept “Science
Technology &amp; Research” belongs to the
concept scheme “Governance Sector” and is
associated with the organisation “Science and
Technology Department West Bengal”.</p>
    </sec>
    <sec id="sec-2">
      <title>5. Generating Bharathi</title>
      <sec id="sec-2-1">
        <title>Bharathi is built using a semi-automated ex</title>
        <p>traction pipeline that periodically crawls the
Government of India web sites mentioned in
Section 3, annotates the semantic entities and
serializes the knowledge graph tuples in the
form of a N-Triples file 17. The knowledge
graph is generated inline with the Bharathi
model explained in Section 4. Each of these
steps is explained in detail below:
5.1. Extraction of Metadata</p>
      </sec>
      <sec id="sec-2-2">
        <title>The source files exists in the form of either</title>
        <p>HTML pages or CSV (Comma Separated
Values) files. The extractor is customised for
each of the source web sites to take care of
the specific nuances and organisation of
information within the respective source web
site. Note that this feature of the extraction
pipeline can be extended in the future to
include more sources of web sites as identified.</p>
        <p>The information extracted mainly consists of
the government entity, its descriptors (such
as name, URL, abbreviations), the
classification of the organisation and the list of sub
organisations. This information is consolidated
from various sources into a large single data
set (CSV file). The information regarding
sector, sub sector and related topics is extracted
into a separate CSV dataset as this data
structure is diferent from the extraction format
used for the government organisations.</p>
        <p>The administrative regions, sectors,
topics and other organisations do change
periodically (name changes, addition of new
districts etc.). These changes are handled
using the Provenance Ontology18. Wherever
the source mentions a version, the same is
recorded in Bharathi with a history of
activity that triggered the change. URL links
17https://www.w3.org/TR/n-triples/
18PROV-O: The PROV Ontology –https://www.w3.
org/TR/prov-o/
generated for the Bharathi entities are static. used to create and serialize the tuples
usThey don’t change for the entities once de- ing the Bharathi ontology definitions
disifned in Bharathi thus assuring continuity to cussed in Section 4. Unique persistent URLs
the users of Bharathi. are generated for each instance following
the RDF principles. The knowledge graph
5.2. Entity Annotations can be accessed at http://semanticwebindia.
in/bharathi/BharathiKG. Figure 2 illustrates
A unique entity is created for each new in- the overall architecture for the generation of
stance of a government organisation or a the Bharathi knowledge graph.
classification depending upon the attributes
of the entity extracted. GeoNames web
services are used to link administrative regions 6. Real World Applications
to its corresponding GeoNames feature. The using Bharathi
entity annotation routine is sensitive enough
to detect that entities with the same label We present two real world applications using
(hasName or prefLabel) need not represent the Bharathi knowledge graph.
the same entity in the Bharathi knowledge
graph. For eg. “Chandigarh” is a Union Ter- 6.1. Web Interface to Bharathi
ritory, a District as well as a Smart City in
India. To distinguish this aspect, surrounding This is a web application interface for users
attributes of the extracted information from outside the scientific community to search,
the source web site are used to make the dis- browse and explore the entities and their
retinction. We use three versions of the Entity lationships in Bharathi. The users are
alAnnotator, one each for government organi- lowed to search for a particular entity or find
sations &amp; administrative regions, one for or- it through one of its classifications. The
inganisation classifications and one for gover- formation is organised in a hierarchical
mannance sectors and topics. ner to understand the hierarchical
classification of each entity in the government
func5.3. Serialization of the tion. Further, the linked entities can be
traKnowledge Graph versed just as reaching out from one link to
the other in a web page. Each page
regardWe have created a Python 3.6 script to ing a government organisation or an
admingenerate the N-Triples (.nt) file using the istrative region or a classification presents a
CSV file generated in the extraction step. consolidated identity to the entity. This is
SPARQL wrapper rdflib routines have been an important feature of Bharathi. Most of
the metadata used for the Indian context is “Chandigarh - Smart City”. The right pane
spread across many sources with the same of the functional page shows the hierarchy
administrative region sometimes referred by of the selected entity.
its code or its various names or its
abbreviation. 6.2. Semantic Covid19 India</p>
        <p>Further, provenance history is Analysis
available for public view at http:
//semanticwebindia.in/bharathi/download. This application has been built by
harnessAlso, version history for a semantic entity in ing the semantic framework of Bharathi.
Bharathi can be viewed at its functional link Covid 19 datasets are sourced from
multie.g. (http://semanticwebindia.in/bharathi/ ple public data sources such as https://www.
home?id=14900&amp;type=org). A feedback covid19india.org/ for covid data related to
Inpage has been provisioned to capture the dia and https://datahub.io/core/covid-19 for
user’s inputs on how the information can covid data related to other countries. A
debe enhanced with additional metadata from tailed entity disambiguation routine
identiother sources. Figure 3 shows the landing ifes the linkable semantic entities from the
page of Bharathi for the external user. Users raw Covid19 datasets. The Covid19
indicacan search for an administrative region, tors such as “Total Confimed”, “Total
Degovernment organisation or a sector / sub ceased”, “Total Recovered”, “Total Tested”
sector. Bharathi also holds a modest set of etc. were created as sub topics under the
common topics found in public data sites Sector - “Health”, “Sub Sector” - "Covid19".
published by the government. Figure 4 Each dataset refers to a geographical
locashows the functional page for the entity tion for which the indicators have been
collected and these could be at the state or the erarchy of the administrative regions, with
sub state Level (eg. districts, cities). These ge- minimal efort, the Covid19 application
facilographical entities are the administrative re- itates aggregation of the various indicators
gions already existing in Bharathi. Using the at the state level (all districts within a state
semantic links of the administrative regions have a hierarchical relation to their parent
with GeoNames resources and their classi- state) and analysis of Covid19 transmission
ifcations such as “State” or “District” in In- across states sharing boundaries. The
DBpedia, we are able to answer complex intuitive dia knowledge graph is linked to the
GeoNCovid19 Analysis questions such as 1) What ames knowledge base and the GeoNames
enis the trend of “Total Confirmed Cases” in tities are linked to Bharathi administrative
the neighbourhood of “District” Coimbatore regions. Therefore, this semantic link
en(a district in the state of Tamil Nadu in India) ables us to explore the efect of Covid
transwithin a distance of 100 km. 2) How do states mission across states sharing boundaries.
with comparable population density fare on Figure 5 and Figure 6 show a
the “Number of Deaths” in a given time pe- glimpse of Covid19 Analysis India
riod? 3) What are the indicators in the family application and can be accessed at
of “Testing Indicators” that can be compared http://sandhicovid.semanticwebindia.com/.
for a given region and timeline? Each of the
above questions is answered by linking the Analysing Covid19 events :
Conceptuadditional metadata from related knowledge ally an event brings together an activity or
graphs using the linked data properties of the a milestone, a location and a time period in a
Bharathi knowledge graph. single entity. We extended the “Event Class”
Additionally, using the classification
hifrom the Event ontology19 to define a cus- data available in the Bharathi knowledge
tom “Event” in the Sandhi Covid19 applica- graph. Thus Bharathi enables advanced
analtion. Apart from the usual attributes inher- ysis based on entity-centric search,
exploited from the standard event ontology, we in- ration and information discovery through
troduced object properties for “predecessor” the linked data properties of the underlying
and ”successor”, thus enabling an in-depth knowledge graph.
analysis of related events in the Covid19
timeline. “Lockdown 1.0”, “Lockdown 2.0” 6.3. Sample SPARQL queries to
etc. were created as individual instances the Bharathi Knowledge
of the extended Event class. The
semantics facilitated by these linked entities enable Graph
a detailed “Event Based Analysis” using the Here we present an assorted list of SPARQL
Covid19 data. queries to the knowledge graph and describe</p>
        <p>Figure 7 shows “Event Based Analysis” their expected result.
feature of Covid19 Analysis India applica- The SPARQL query in Table 1 returns all
tion. the top level organisation classifications in</p>
        <p>Note that this semantic layer can be ex- the Government of India.
tended to any collection of open datasets The SPARQL query in Table 2 returns
containing entities pertaining to the Indian all the States and Union Territories of
Incontext that can be linked to the meta- dia along with their lat-long coordinates by
linking Bharathi knowledge graph with the
19The Event Ontology: http://motools.sourceforge. GeoNames knowledge base.
net/event/event.html</p>
        <sec id="sec-2-2-1">
          <title>Knowledge Graph – Compare a Neighbourhood</title>
          <p>the government organisations and their sub
organisations belonging to the classification
- "Legislature of India".</p>
        </sec>
        <sec id="sec-2-2-2">
          <title>Union Territories of India along with their lat-long coordinates by linking Bharathi knowledge graph with the GeoNames knowledge base</title>
          <p>PREFIX gn: &lt;http://www.geonames.org/ontology#&gt;
PREFIX skos: &lt;http://www.w3.org/2004/02/skos/core#&gt;
PREFIX bhorg: &lt;http://semanticwebindia.in/bharathi/ont/org/&gt;
PREFIX org: &lt;http://www.w3.org/ns/org#&gt;
PREFIX wgs84_pos: &lt;http://www.w3.org/2003/01/geo/wgs84_pos#&gt;
select ?org1 ?gc ?classname ?name ?lat ?long
where
{
?org1 a bhorg:Organisation. ?org1 bhorg:hasName ?name.
?org1 bhorg:hasSpatial ?gc.
?org1 org:classification ?c.
?c skos:prefLabel ?classname. FILTER (?classname IN
("State", "Union Territory", "National Capital Territory")).
?gc wgs84_pos:lat ?lat.
?gc wgs84_pos:long ?long
}
order by ?name</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>7. Conclusions and Future</title>
    </sec>
    <sec id="sec-4">
      <title>Work</title>
      <p>Comparisons with DBpedia : DBpedia
We have introduced Bharathi - Linked Data is project to convert structured content of
Vocabulary for the Indian context, which fa- Wikipedia into linked data and does contain
a lot of information regarding India
documented in Wikipedia. However, this
information is largely incomplete and does not
align with some of the most credible updates
published by the Government of India (GoI)
websites. Bharathi is an efort to exclusively
extract information from GoI websites and
maintain its currency.</p>
      <p>There are several limitations of the
Bharathi knowledge graph that are the
focus of ongoing and short-term eforts.</p>
      <p>Bharathi can be enriched with reasoning
statements from the OWL vocabulary to
enable reasoning and creation of new facts
using reasoners such as Apache Jena. We
also intend to extend the content of our
graph to other sources of information in
collaboration with the Government of India
to facilitate a larger variety of instances in
Bharathi. Finally, our continued eforts on
Bharathi knowledge graph aims to build a
multi-lingual search across Indian languages
to enable larger support and patronage for
Bharathi.</p>
    </sec>
  </body>
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