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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>IWSG</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>The Science Library: A Controlled Natural Language driven Science Gateway</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>Eunjin Lee</institution>
          ,
          <addr-line>Dave Braines</addr-line>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2019</year>
      </pub-date>
      <volume>12</volume>
      <fpage>12</fpage>
      <lpage>14</lpage>
      <abstract>
        <p>-The International Technology Alliance in Distributed Analytics and Information Science (DAIS-ITA) is a research program conducting fundamental research across a consortium of organizations from academia, industry and government in the US and UK. A key output of the program are the academic publications, and from these a rich social and topical network between authors and organizations emerges. To capture and convey this we have created the publicly available Science Library as a user-centric, interactive portal. The Science Library is a Controlled Natural Language (CNL) driven research gateway, which allows the community to explore and query the publications and networks through an open, webbased application. The data is represented through interactive visualizations along with the ability for users to query the model using a natural language conversational interface. The CNL based approach models the data through concepts, properties and relationships which are defined using CNL and are therefore both human readable and directly machine processable. This captures complex semantics in a simple format and enables nontechnical users to participate in the continuous improvement of the data model behind the Science Library application. This paper presents the features, implementation and design considerations of the Science Library and the underlying CNL implementation.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>I. INTRODUCTION</title>
      <p>
        When publishing a broad body of scientific research, we
believe that it is important to retain some of the contextual
information about the relationships between the papers, authors
and topics. This helps the reader to understand the “bigger
picture” behind each paper, beyond the traditional information
captured in the references and citations. The International
Technology Alliance in Distributed Analytics and Information
Science (DAIS-ITA) [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] is a research program conducting
fundamental research across a consortium of organizations
from academia, industry and government in the US and UK.
For this program, and the previous Network and
Information Science (NIS) ITA [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] we created a large long-running
multi-disciplinary research team from multiple organizations
who are encouraged to pursue collaborative research across
organizational, national and disciplinary boundaries. In this
context, recording the wider organizational, topical and social
context of the papers is a key consideration for us in measuring
additional impacts and effects of the work.
      </p>
      <p>
        In this paper we describe the Science Library1 application,
1The live Science Library for the DAIS ITA research program can be
accessed at http://sl.dais-ita.org/science-library
Copyright © 2021 for this paper by its authors. Use permitted under Creative
Commons License Attribution 4.0 International (CC BY 4.0).
and give examples of the various interactive visualizations
that enable the visitor to explore the rich knowledge graph of
research publication information. We believe that the approach
we have taken supports the idea of Cognitively Mediated
Research Discovery [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] both in terms of the interactive
visualization and search capabilities provided, but also in the
way in which the underlying information is modelled, captured
and shared. By this we mean that we are exposing multiple
perspectives by which a reader might explore a particular
research domain; able to follow different pathways between
papers and authors to navigate the cognitive space.
      </p>
      <p>To achieve this in a realistic timeframe we used the
advantages available when developing such semantic knowledge
graphs using a Controlled Natural Language (CNL), and
we describe this CNL-based implementation of the Science
Library in this paper. We also described the high-level
architecture of the Science Library system, and the technique
we use to solicit publication information from the DAIS ITA
community for publishing.</p>
      <p>The Science Library solution is built using technology
from our earlier research (Controlled English) but the Science
Library solution itself has not been reported in detail in any
of our publications to date. The previously published work
introduces the Science Library at a high level while this
paper explores how this solution provides flexibility through
the knowledge graph and the ability to explore complex
relationships. Hence this paper describes the implementation
of the Science Library and the potential power of the approach
when using a Controlled English based solution. The Science
Library currently handles 9,000 nodes, with approximately
40,000 links and 60,000 property values. It contains over 250
papers, approximately 300 authors and over 60 organizations.
The site is publicly available and gets up to 50 active users
per day.</p>
      <p>In Section II we explore the various ways to interact with the
complex knowledge graph through visualizations accompanied
by the motivations behind them and in Section III we explain
the CNL basis for the application, and the conceptual model
schema that underpins the work. In Section IV we discuss
existing work related to using CNL to drive Science Gateways
and in Section V we talk about our future plans for the
environment as the DAIS ITA program continues. Section VI
concludes the paper.</p>
    </sec>
    <sec id="sec-2">
      <title>II. INTERACTION WITH THE KNOWLEDGE GRAPH</title>
      <p>Like many research groups or programs, one key output are
the academic publications created as a result of the research.
From these a rich social and topical network between authors
and organizations emerges, and since the DAIS ITA is focused
in particular on fostering a deep collaborative mind-set it is
important for us to understand and explore this aspect of our
work. To capture and convey this body of published research,
for example as shown in the Author narrative timeline in
Figure 1, we have created the publicly available Science
Library2 as a user-centric, interactive portal. The idea for
the Science Library originally came from the earlier NIS
ITA research program, and was originally developed and
deployed3 for that purpose, but has been reused and extended
for this later DAIS ITA research program. The Science Library
is a Controlled Natural Language (CNL) driven research
gateway, which allows the community to explore and query
the publications and networks through an open, web-based
application built on a complex semantic knowledge graph.
The data is represented through interactive visualizations along
with the ability for users to query the model using a natural
language query interface. The CNL based approach models
the data through concepts, properties and relationships which
are defined using CNL and are therefore both human readable
and directly machine processable. This captures complex
semantics in a simple format and enables non-technical users to
2Science Library for DAIS ITA (Distributed Analytics and Information
Science International Technology Alliance), http://sl.dais-ita.org/science-library/
3Science Library for NIS ITA (Network and Information Science
International Technology Alliance, http://nis-ita.org/science-library/
participate in the continuous improvement of the data model
behind the Science Library application. This paper presents
the features, implementation and design considerations of the
Science Library and the underlying CNL implementation.</p>
      <p>Fig. 2. List of publications</p>
      <p>One primary purpose of the Science Library is the
exploration of publications from a given research program, such as
the DAIS ITA. Figure 2 shows a simple list of publications
that can be sorted by various criteria including: age, name
and citation count. Additional information is available on this
page, such as an overall summary of the publications for the
program, broken down into publication type (journal, external
conference, internal conference, technical report or patent).
Each publication has a colored icon to indicate the paper
type, and any paper variants are indicated by stacked icons.
For example, it is often the case that an original journal or
conference publication will be summarized or reworked into
an internal conference publication for presentation to the DAIS
ITA research community at the annual meeting of the alliance.</p>
      <p>Throughout the Science Library application all entities can
be clicked on to take the user to a page that shows the
details about that particular entity. In Figure 3 we show the
publication details page which provides a large thumbnail
image of the paper and the ability to download all relevant
information regarding that publication (e.g. the paper PDF,
any presentation slides, poster, or other supporting material).
We also display the author information, the title and abstract
and any venue information, including the location at which
the paper was presented (for conference papers). All of this
information is available in the semantic knowledge graph
that underpins the system and is available for searching or
exploration of the graph.</p>
      <p>Figure 1 shows a narrative timeline for the publications
of any author. The visualization shows the development of
research ideas and topics over time, along with co-authorship
sub-groups. Users can read this visualization from left to right,
with each node on the network being a particular publication
at a point in time and the links between them showing
coauthorship flows between the papers. This can be particularly
useful to determine when new threads or topics form
partway through the research, and how they manifest in terms of
publications over time.</p>
      <p>Building on this is the more traditional co-authorship chart
shown in Figure 4. The nodes represent authors, indicated
by their initial (e.g. “DB” for Dave Braines), and links to
other authors who they have co-authored with. The weight of
the links indicate the number of times that co-authorship has
occurred, and this also drives the proximity of the nodes. In
the interactive visualization, users can hover over particular
links to have them highlighted, and have information about
the author in question appear over the node. This is
particularly useful for highlighting common co-authorship subgroups,
which often indicate particular topics or threads of work that
subsets of authors regularly publish. The colors of the nodes
indicate whether an author is from academia, industry, or
government.</p>
      <p>Sometimes it is useful to see the specific publications
for a pair of co-authors, i.e. only those papers for which
both authors are involved. This is shown in Figure 5 and is
represented as a stacked bar chart over time, with the bars
representing the papers of a particular type. Hovering over any
bar shows the individual papers for that period, enabling the
user to click through to see their details. This is a very similar
visualization to the one used for displaying the publications
for any given organization and seems to give good insight for
this particular perspective. It is worth noting however that the
visualizations chosen for each view are purely subjective based
on our informal opinion as to what “works best” for the given
situation and is not according to any scientific basis.</p>
      <p>In Figure 6 we show the visual aspects of a particular
event mainly to showcase that we have the geo-spatial data,
rather than it being a particularly useful view. We show
the event venue as a large yellow circle, and the authors
of the publications at this event (color coded according to
their organization type) are shown in the geographic location
associated with their organization.</p>
      <p>Each page also has a simple search bar at the bottom of
the screen. This will accept any search terms from the user
and performs a reasonably complex semantic search into the
semantic knowledge graph. If the terms that are searched for
result in matches to specific named instances then the result
shown to the user is the relevant page on which this
information can be located. For example, the search term “Dave
Braines co-authors” will return a result which is the author
page for Dave Braines in the co-author graph mode. In the
event that multiple matches are made, or matches are made to
which there is no pre-defined visualization type, then a simple
list of clickable links (to papers, authors, organizations, topics
etc) are shown. The search is based on a combination of fuzzy
keyword searching (to match title and abstract terms) as well
as semantic graph searching. This capability is underpinned by
the “Hudson” natural language search APIs4 which provide
a rich JSON response indicating which concepts, properties
or instances were matched in the semantic knowledge graph
based on the query terms used. There is a lot of additional
power that can be gained from using this approach which is
not yet implemented into the system. For example the ability
to ask questions such as “list authors who have written papers
with someone from industry on the topic of IoT before 2018”.
Today the interpreter API will match all of the terms in this
question to the corresponding features in the semantic graph,
but we have not yet developed a suitable “answerer” capability
to take this interpretation and show the result to the user in a
meaningful way.</p>
      <p>In all of these visualizations we have designed a very simple
user experience and have tried to showcase a variety of visual
techniques to communicate certain aspects of the information
in the underlying semantic knowledge graph. There is far more
information available in the graph than we are making use
of (See Figure 7), and it would be possible in the future to
create a much richer set of visualizations if time permits. See
Section V for some discussion about our plans for possible
future extensions to this work.</p>
    </sec>
    <sec id="sec-3">
      <title>III. BUILDING THE SCIENCE LIBRARY</title>
      <p>
        All of the visualizations and interaction features described in
the preceding section are implemented using traditional web
development technologies using HTML, CSS and Javascript
(client and server side),and they could be integrated with any
suitable back-end database-like system. The real novelty in
our approach comes in the technology used to implement the
semantic knowledge graph, which drive the visualizations and
allow users to easily contribute to, and extend, the model.
To achieve this, we use a Controlled Natural Language (CNL)
technology named Controlled English (CE), which we defined
and developed in previous research [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] in order to provide
agile knowledge representation and reasoning capabilities like
those available in the Semantic Web stack. CE is a constrained
form of English that is easy for non-technical human users to
read, and it is possible for them to write it too (it’s harder
to write, but still less technical than traditional alternative
machine formats such as RDF/OWL). CE is a language that
is both the human friendly language and the directly
machineprocessable language at the same time. There is no need to
convert CE into some technical form (such as RDF or JSON)
for the machine to process it. It is directly processed in its
original readable English form. This is a key differentiating
factor to our approach, and is why it is so agile as an ontology
development and semantic graph building language.
      </p>
      <p>The following CE examples taken from the Science Library
illustrate the structure and readability of the sentences used
to rapidly build up the concepts and relationships in the
knowledge graph:
there is a person named 'dave_braines' that
has 'Dave' as forename and
has 'Braines' as surname and
has 'Dave Braines' as full name and
has the organisation 'IBM UK' as default
organisation and
has 'https:/.../dave_braines.jpg' as profile
picture.
the person 'dave_braines' has the person
'alun_preece' as co-author.
there is a document named 'doc-1009' that
is a external conference paper and
has 'A Generative Model For Predicting
Terrorist Incidents' as title and
applies to the programme 'DAIS-ITA' and
has the event 'SPIE DSS 2017' as venue and
has the project 'IPP16P4' as project.
the published person 'dave_braines'
wrote the document 'doc-1276'.</p>
      <p>
        We operationalize the CE language in the open source
ce-store5 library which is a simple Java-based web-services
component to allow developers to easily integrate with CE
knowledge graphs using REST APIs that are familiar to them
4Hudson natural language apis for the ce-store,
https://github.com/cestore/ce-store/wiki#hudson
5ITA Controlled English store (ce-store),
https://github.com/ce-store/cestore
from using other technologies. For the developer we want the
environment to be as familiar and easy to use as possible, even
if they don’t need to know that the underlying implementation
is CE. In our previous research we have written extensively
about the use of CE and ce-store in a variety of settings directly
relevant to the usage in this paper. In [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] we define a
conversational mechanism using this approach which enables users to
converse with the underlying knowledge graph using natural
language queries, and this is what led to the development of the
“Hudson” APIs (mentioned in the Section II) which underpin
the Science Library semantic search capability.
      </p>
      <p>
        The ability to rapidly define conceptual models in
realtime to support the capture of complex semantic data came
from our field trial work on various exercises, for example
as reported in [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. This evolved in various directions, one of
which was the highly extensible capture of biographical and
social information to aid human decision-making [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] and this
led us directly to the idea for building the Science Library to
capture our own contextual and social network for our research
publications.
      </p>
      <p>In addition to the core ce-store engine being available
as open source, we have also open sourced the Science
Library user interface6 and the Controlled English conceptual
models that underpin it7. All the components and functionality
presented in this paper can be used freely by other solutions;
the entire approach is open sourced and available for anyone
else to adopt as a separate, stand-alone instance. Full details
and tutorials on how to set up a similar Science Gateway using
6Science library user interface, https://github.com/ce-store/science-library
7Science library data model for DAIS ITA,
https://github.com/ce-store/sldata-dais
CE can be found on the ce-store wiki page8.</p>
      <p>
        It is this ability to rapidly define the underlying semantic
conceptual models and then populate them with corresponding
data that enabled us to build the Science Library application in
a very short amount of time. We were able to develop simple
models quickly, populate a small amount of data and then
build some example visualizations in a very rapid manner.
The flexibility to modify and extend the concepts, properties
or instances in the underlying graph gave us a very fluid
environment in which we could rapidly explore new ideas and
new conceptualizations before finalizing on those that worked.
In Figure 8 we show the high-level conceptual model for the
Science Library. Key concepts are document (an academic
publication), ordered author (an authorship of a paper), person
(an individual who may author multiple papers) , organization,
event and so on. Each of these concepts has one or more named
relationships to other concepts, or textual attributes (such as
title or abstract) which are collectively known as properties.
These concepts and properties which are the equivalent of a
conceptual graph [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] and the semantics are added through the
definition of inheritance and the specification of logical
inference rules. We use numerous rules in our conceptual model
to infer additional information. Many times, this is simply
to more fully connect the graph to enable the development
of the visualizations to be more straightforward, but in many
cases they also add significant additional “logical value” to
the model. For example we infer co-authorship from paper
authorship: If two authors write the same paper then they are
inferred to be co-authors.
      </p>
      <p>In Figure 9 we show the implementation of the system,
8ce-store wiki and tutorials, https://github.com/ce-store/ce-store/wiki
and how the information flows from our private content
management system into the public Science Library application.
We have designed a system to place minimum administrative
burden on our consortium of paper authors, enabling them
to simply provide a PDF of their publication, and we as
administrators manually extract all of the required information
(authors, venue, organizations etc) in order to publish this on
their behalf.</p>
      <p>Once the paper authors upload a PDF to the Drupal based
content management system, the administrators manually
create an instance of a Science Library publication and add the
related properties. A Jpeg thumbnail of the paper is generated
using the PDFBox tool and the citation statistics are manually
pulled from Google Scholar and also added to the Science
Library publication instance.</p>
      <p>The ce-store engine is run to ingest and generate CE for
the new publications and to update the existing instances and
relationships. Finally, the Science Library makes calls to the
ce-store semantic knowledge graphs via simple REST APIs
to generate the visualizations of relationships and present the
data to the user on the interactive website.</p>
    </sec>
    <sec id="sec-4">
      <title>IV. RELATED WORK</title>
      <p>
        There is limited literature around the use of CNL to
drive Science Gateways and interactive visualizations, however
methods to allow users to quickly and easily contribute to
ontologies using CNL are known [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. There are also
several techniques which help users to explore and query
ontologies using other forms of Controlled English. These
methods allow users to query a knowledge graph using CNL,
such as Attempto Controlled English [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. Semantic Wikis
capture knowledge about the data within pages and the
relationship between pages, which allow semantic querying of the
data. Some semantic wikis export the ontologies of the wiki
as RDF or OWL, and parse it to a CNL to enable queries [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]
[
        <xref ref-type="bibr" rid="ref13">13</xref>
        ].
      </p>
      <p>
        Domain representation in general aims to effectively present
the relevant information to users from a complex and vast set
of data. There are various techniques and workflows to
visualize digital networks. A key aspect of domain representation
lies in the ability to allow the user to explore the data and
understand the relationships between entities in an intuitive
way. An example technique is visually presenting the semantic
relationships between entities alongside an ordered list to give
the user a wider perspective of the data [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ].
      </p>
    </sec>
    <sec id="sec-5">
      <title>V. FUTURE PLANS</title>
      <p>We are continually improving the Science Library and the
underlying technologies which underpin the project. One such
improvement is to enhance the user interface of the website to
make it accessible from any device, including mobile phones
and tablets.</p>
      <p>A better solution to link directly to an external citation
source that can return the citation data in a structured form, to
allow computation and processing within the Science Library
will be developed to replace the current manual system of
collecting data from Google Scholar.</p>
      <p>We are also planning to improve the way the new instances
in the ce-store model get created as well as updated, to
improve the efficiency of the publishing process. A Node.js
based tool will enable generation of new instances and link
to existing instances (e.g. people, organisations, projects).
This will enable us to publish to the Science Library more
effectively by automatically generating the required CE.</p>
    </sec>
    <sec id="sec-6">
      <title>VI. CONCLUSION</title>
      <p>The Science Library holds the publication information of the
DAIS-ITA research program and provides the community with
an interactive, visual web portal to view this data. It presents
contextual information about the relationships between papers,
authors and topics alongside the traditional information
captured in the references and citations. Users are able to interact
with the rich body of information in different forms including
lists, relationship graphs and timelines to better understand the
wider context of the publication, authors and topics.</p>
      <p>ITA Controlled English was used to capture and generate the
semantic knowledge graph which drives the Science Library.
Since CE is language that is both machine processable and
human readable at the same time, it has been the key in how
we were able to implement and rapidly develop this Science
Gateway. We have open sourced the core ce-store engine as
well as the entire Science Library user interface to share this
flexible framework with the wider scientific community.</p>
    </sec>
    <sec id="sec-7">
      <title>ACKNOWLEDGMENT</title>
      <p>This research was sponsored by the U.S. Army Research
Laboratory and the UK Ministry of Defence under Agreement
Number W911NF-16-3-0001. The views and conclusions
contained in this document are those of the authors and should
not be interpreted as representing the official policies, either
expressed or implied, of the U.S. Army Research Laboratory,
the U.S. Government, the UK Ministry of Defence or the UK
Government. The U.S. and UK Governments are authorized
to reproduce and distribute reprints for Government purposes
notwithstanding any copy-right notation hereon.</p>
    </sec>
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