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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>WoPeD goes NLP: Conversion between Workflow Nets and Natural Language</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>Thomas Freytag, Cooperative State University (DHBW) Karlsruhe, Germany Philip Allgaier, bpcompass GmbH</institution>
          ,
          <addr-line>Karlsruhe and Hamburg</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>WoPeD (Workflow Petrinet Designer) is an open-source Java software for designing business processes in terms of workflow nets, a common extension of Petri nets. This demo lays the focus on two recently added features making use of Natural Language Processing (NLP) algorithms in order support the conversion of a graphical process model into a textual process description and vice versa.</p>
      </abstract>
      <kwd-group>
        <kwd>Petri net tool</kwd>
        <kwd>workflow nets</kwd>
        <kwd>NLP</kwd>
        <kwd>Process2Text</kwd>
        <kwd>Text2Process</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>NLP and BPM
Graphical process modeling languages have become an industry standard,
allowing various stakeholders to collectively create visual process descriptions on
a conceptual level. However, graphical models frequently co-exist with informal
textual process descriptions, be it for lack of skills or tools or time to create</p>
      <sec id="sec-1-1">
        <title>1 www.apromore.org</title>
        <p>a graphical model or because a text-based description is required for a
process handbook as sometimes mandated by QA agencies. This has brought up
the question in BPM research transforming these two process representations
into each other, i.e. to automatically generate the textual equivalent of a given
graphical process model and to automatically generate an appealing visual
process model from a given textual representation. There are interesting practical
use cases for this functionality, e.g. to check the mutual compliance between a
textual and graphical version of a business process or to facilitate the inclusion of
visually impaired persons in process modelling activities by providing them with
a text-based interface for understanding and describing a business process. The
following two sections give an overview of how NLP algorithms have been
integrated into WoPeD: Firstly, to export the current process editor contents into
readable English text (“Process2Text”) and secondly to synthetize an workflow
net from a given verbal process specification (“Text2Process”).
3</p>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>Process2Text: Verbalization of a Workflow Net</title>
      <p>
        In [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ], an NLP-based approach has been introduced taking a BPMN diagram as
input and generating a naturual language text as output describing the modelled
behavior. Figure 1 shows the outline of the underlying algorithm. In the first step,
called “Text Planning”, the relevant linguistic information is extracted from the
workflow-net-based process model, mainly by analyzing labels of model elements,
control flow dependencies and task resource assignments.
      </p>
      <p>The analysis is done by two freely available standard NLP tools, Stanford
Tagger2 and WordNet3. The result is converted into a Refined Process Structure
Tree (RPST), a generic data structure to represent components of a process</p>
      <sec id="sec-2-1">
        <title>2 http://nlp.stanford.edu/software/lex-parser.shtml</title>
      </sec>
      <sec id="sec-2-2">
        <title>3 http://wordnet.princeton.edu</title>
        <p>
          graph being introduced in more detail e.g. in [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ]. After applying various heuristics
to restructure and fine-tune the RPST, the second major step of the algorithm
“Sentence Planning” is applied. Here, the leaves of the RPST are processed and
enriched with semantic information derived from the control flow in the graph.
After an additional refinement of the text fragments, a realizer tool (used here:
RealPro [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ]) is applied in order to generate a naturally-sounding English text.
        </p>
        <p>
          The implementation in WoPeD takes major parts of the solution presented
in [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ], however making the transformation process applicable to workflow nets
instead of BPMN diagrams and embedding the algorithm into the WoPeD
process editor by displaying the generated text together with the process graph.
Figure 2 shows a screenshot of the WoPeD editor with a graphical model and a
“Process2Text” sidebar containing the auto-generated text. The associated
process elements are highlighted once the user clicks on a specific text item line in
the sidebar (shown in red).
4
        </p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Text2Process: Generate a Workflow Net from Text</title>
      <p>
        The opposite direction of the transformation is based on an algorithm
welldocumented e.g. in [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] and [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. The transformation uses the same freely-available
NLP tools as the Process2Text algorithm above. As a first step, the input string
is analyzed by the Stanford parser tool and split up into sentences and words
according to the underlying grammar rules. The subsequent steps make use of
two semantical word databases WordNet (see above) and FrameNet 4.
      </p>
      <sec id="sec-3-1">
        <title>4 http://framenet.icsi.berkeley.edu/fndrupal</title>
        <p>This mainly identifies the semantically relevant elements of the textual
process model (e.g. actors, actions, business objects). The result is written into a
data structure called WorldModel where all contributing model elements and
their interrelations are stored. The WorldModel is converted into PNML, the
standard XML-based representation for workflow nets. The last step is to open
up a new WoPeD editor window and create coordinates for the automatically
generated model by calling WoPeD’s built-in layout beautifier. Figure 3 roughly
visualizes the algorithm. Figure 4 shows a screenshot of the dialog for entering
the textual process description (either by typing in or by uploading a text file)
and below the resulting auto-generated and auto-layouted workflow net.
5</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Conclusion and Outlook</title>
      <p>The above features are still in an experimental stage suffering from the general
problem of semantical ambiguities in natural language processing in both
directions. However, the plan is to improve the transformation quality in future
releases of WoPeD. The software is open source and can be downloaded from
the homepage5 or directly from Sourceforge6.</p>
      <sec id="sec-4-1">
        <title>5 www.woped.org</title>
      </sec>
      <sec id="sec-4-2">
        <title>6 www.sourceforge.net/projects/woped/</title>
      </sec>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          [1]
          <string-name>
            <surname>Van der Aalst</surname>
            , W.M.P.; van Hee,
            <given-names>K.M.</given-names>
          </string-name>
          : Workflow Management: Models,
          <string-name>
            <surname>Methods</surname>
          </string-name>
          , and Systems MIT Press 2002.
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          [2]
          <string-name>
            <surname>Freytag</surname>
            ,
            <given-names>T.</given-names>
          </string-name>
          ;
          <string-name>
            <surname>Sänger</surname>
            ,
            <given-names>M.:</given-names>
          </string-name>
          <article-title>WoPeD - An Educational Tool for Workflow Nets</article-title>
          . BPM demo session
          <year>2014</year>
          . http://ceur-ws.
          <source>org/</source>
          Vol-
          <volume>1295</volume>
          /paper3.pdf, accessed
          <year>June 2018</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref3">
        <mixed-citation>
          [3]
          <string-name>
            <surname>Freytag</surname>
            ,
            <given-names>T.</given-names>
          </string-name>
          ;
          <string-name>
            <surname>Allgaier</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          <string-name>
            <surname>Burratin</surname>
            <given-names>A.</given-names>
          </string-name>
          ;
          <string-name>
            <surname>Danek-Bulius</surname>
            ,
            <given-names>A.</given-names>
          </string-name>
          :
          <string-name>
            <surname>WoPeD - A “</surname>
          </string-name>
          Proofof-Concept”
          <article-title>Platform for Experimental BPM Research Projects</article-title>
          .
          <source>BPM demo session</source>
          <year>2017</year>
          , http://ceur-ws.
          <source>org/</source>
          Vol-1920/BPM_2017_paper_190.pdf, accessed
          <year>June 2018</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref4">
        <mixed-citation>
          [4]
          <string-name>
            <surname>Reijers</surname>
            ,
            <given-names>H.A.</given-names>
          </string-name>
          ;
          <string-name>
            <surname>Freytag</surname>
            ,
            <given-names>T.</given-names>
          </string-name>
          ;
          <string-name>
            <surname>Mendling</surname>
            ,
            <given-names>J.</given-names>
          </string-name>
          ;
          <string-name>
            <surname>Eckleder</surname>
            ,
            <given-names>A.</given-names>
          </string-name>
          :
          <article-title>Syntax highlighting in business process models</article-title>
          .
          <source>Decision Support Systems</source>
          <volume>51</volume>
          (
          <issue>3</issue>
          ):
          <fpage>339</fpage>
          -
          <lpage>349</lpage>
          (
          <year>2011</year>
          ).
        </mixed-citation>
      </ref>
      <ref id="ref5">
        <mixed-citation>
          [5]
          <string-name>
            <surname>Mendling</surname>
            ,
            <given-names>J.</given-names>
          </string-name>
          :
          <source>Metrics for Process Models</source>
          , Springer Verlag, Berlin,
          <year>2008</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref6">
        <mixed-citation>
          [6]
          <string-name>
            <surname>Leopold</surname>
            ,
            <given-names>H.</given-names>
          </string-name>
          ;
          <string-name>
            <surname>Mendling</surname>
            ,
            <given-names>J.</given-names>
          </string-name>
          ;
          <string-name>
            <surname>Polyvyanyy</surname>
            ,
            <given-names>A.</given-names>
          </string-name>
          :
          <article-title>Generating Natural Language Texts from Business Process Models</article-title>
          . In: Ralyté,
          <string-name>
            <given-names>J.</given-names>
            ,
            <surname>Franch</surname>
          </string-name>
          ,
          <string-name>
            <given-names>X.</given-names>
            ,
            <surname>Brinkkemper</surname>
          </string-name>
          ,
          <string-name>
            <given-names>S.</given-names>
            ,
            <surname>Wrycza</surname>
          </string-name>
          , S. (eds)
          <article-title>Advanced Information Systems Engineering</article-title>
          . CAiSE
          <year>2012</year>
          . LNCS, vol
          <volume>7328</volume>
          . Springer, Berlin, Heidelberg
          <year>2012</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref7">
        <mixed-citation>
          [7]
          <string-name>
            <surname>Polyvyanyy</surname>
            <given-names>A.</given-names>
          </string-name>
          ;
          <string-name>
            <surname>Vanhatalo J.; Völzer</surname>
            <given-names>H.</given-names>
          </string-name>
          :
          <article-title>Simplified Computation and Generalization of the Refined Process Structure Tree</article-title>
          . In: Bravetti M.;
          <string-name>
            <surname>Bultan</surname>
            <given-names>T</given-names>
          </string-name>
          . (eds) Web
          <source>Services and Formal Methods. Lecture Notes in Computer Science</source>
          , vol
          <volume>6551</volume>
          , Springer, Berlin, Heidelberg,
          <year>2010</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref8">
        <mixed-citation>
          [8]
          <string-name>
            <surname>Lavoie</surname>
            ,
            <given-names>B.</given-names>
          </string-name>
          ;
          <string-name>
            <surname>Rambow</surname>
            ,
            <given-names>O.</given-names>
          </string-name>
          :
          <article-title>A Fast and Portable Realizer for Text Generation Systems</article-title>
          .
          <source>5th Conference on Applied Natural Language Processing</source>
          ,
          <year>1997</year>
          , www.aclweb.org/anthology/A97-1039, accessed
          <year>June 2018</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref9">
        <mixed-citation>
          [9]
          <string-name>
            <surname>Friedrich</surname>
            ,
            <given-names>F.</given-names>
          </string-name>
          ;
          <string-name>
            <surname>Mendling</surname>
            ,
            <given-names>J.</given-names>
          </string-name>
          ;
          <string-name>
            <surname>Puhlmann</surname>
            ,
            <given-names>F.</given-names>
          </string-name>
          :
          <article-title>Process Model Generation from Natural Language Text</article-title>
          . In: Mouratidis H.,
          <string-name>
            <surname>Rolland</surname>
            <given-names>C</given-names>
          </string-name>
          .
          <article-title>(eds) Advanced Information Systems Engineering</article-title>
          .
          <source>CAiSE 2011. Lecture Notes in Computer Science</source>
          , vol
          <volume>6741</volume>
          , Springer, Berlin, Heidelberg
          <year>2011</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref10">
        <mixed-citation>
          [10]
          <string-name>
            <surname>Riefer</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          ;
          <string-name>
            <surname>Ternis</surname>
            ,
            <given-names>S.</given-names>
          </string-name>
          ; Thaler,
          <string-name>
            <surname>T:</surname>
          </string-name>
          <article-title>Mining Process Models from Natural Language Text: A State-of-the-Art Analysis</article-title>
          .
          <source>Processings of Multikonferenz Wirtschaftsinformatik (MKWI-16), March</source>
          <volume>9</volume>
          -11, Illmenau, Germany,
          <year>2016</year>
          .
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>