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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Virtual Worlds as a Model-View Approach to the Communication of Business Processes Models</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Hanwen Guo</string-name>
          <email>hanwen.guo@student.qut.edu.au</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ross Brown</string-name>
          <email>r.brown@qut.edu.au</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Rune Rasmussen</string-name>
          <email>r.rasmussen@qut.edu.au</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Information Systems School, Science and Engineering Faculty</institution>
          ,
          <addr-line>QUT, Brisbane</addr-line>
          ,
          <country country="AU">Australia</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Although business process analysis methods are mature today, business analysts and stakeholders are still hampered by communication issues. We argue that using a virtual world to model a business process can benefit communication activities. We believe that virtual worlds can be used as an efficient model-view approach, increasing the cognition of business requirements and analytic results, as well as the possibility of business plan validation. As an exploration paper, we believe that this promising research can encourage people to investigate more research topics in the interdisciplinary area of information system, visualization and multi-user virtual worlds.</p>
      </abstract>
      <kwd-group>
        <kwd>Virtual World</kwd>
        <kwd>Business Process Management</kwd>
        <kwd>Visualization</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>
        An optimization and improvement process for a workflow system involves an intensive
communication process between the stakeholder and business analyst [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. According to
communication theory [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], a general communication model adapted in the workflow system optimization
and improvement process can be depicted in Fig.1. It is reported that business analysts and
stakeholders often have communication problems [
        <xref ref-type="bibr" rid="ref2 ref3 ref4">2-4</xref>
        ]. On the one hand, stakeholders cannot
always elaborate their business activities in a well structured way [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. On the other hand, the
visual code used by business analysts inevitably has noise, interfering with cognitive processes
in the reader [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ].
      </p>
      <p>
        Thus, it can be concluded that noise exists in the encoding and decoding process,
as well as the visual code, reducing the possibility of stakeholder buy-in to the plan.
As a result, a solution to this problem is to use a semantically transparent code that
can assist the reader in inferring the meaning of a code from its appearance [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
      </p>
      <p>
        Recently, it has been realized that 3D virtual worlds can be applied in social
science [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. This is because its richer visualization representation abilities enable
people to effectively process more information [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. This strongly suggests that 3D
virtual worlds could be a superior process visualization platform, enabling people to
recall and cognate about conceptual and non-conceptual content, facilitating the
communication process in analyzing, modeling and validating organizational structure
and resource behaviors, see Fig. 2.
      </p>
      <p>This paper is organized as follows: Section 2 discusses related work. Section 3
explores the rationality of using a virtual world as an alternative communication
approach. Section 4 uses a case study in the healthcare domain to demonstrate a set of
visualization benefits offered by such a communication approach. At last, Section 5
concludes with a discussion of achievements, and points towards further work.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Related Work</title>
      <p>
        The Entity-Relationship Diagram (ERD) can be used as a hands on modeling
approach for native stakeholders. However, several researchers [
        <xref ref-type="bibr" rid="ref7 ref8">7,8</xref>
        ] pointed out the
inappropriateness of the representation when an ERD is extend with attributes to
represent complex relationships. In addition, Weber [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] concluded that applying an
ontology in the modeling process can increase the understandability and perception of
the information in a conceptual model.
      </p>
      <p>
        However, these researchers did not address the issue that sound professional
knowledge in information systems plays an important role in understanding modeling
results [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ], and we cannot guarantee that every stakeholder has such necessary
knowledge. Compared with these previous works, this paper intends to provide a new
model-view approach that can facilitate communication between stakeholders and
business analysts, by allowing participants to observe actual activities at the operational
level being juxtaposed with a conceptual model.
      </p>
      <p>
        Currently, 3D virtual worlds have become popular research topics in E-commerce
domains. Some researchers [
        <xref ref-type="bibr" rid="ref11 ref12">11,12</xref>
        ] have visualized a process models from the
control, resource and data perspectives in a virtual world. Perkins [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ] proposed an agent
system that plays as an intermediate between a simple workflow engine and a virtual
world for representing human resource behavior. Bogdanovych [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] established a
methodology called Virtual Institutions (VI) to facilitate the communication between
the customer and product sellers, which has a similar purpose to ours.
      </p>
      <p>
        These works [
        <xref ref-type="bibr" rid="ref11 ref12 ref13 ref14">12,11,13,14</xref>
        ] have realized that the virtual world is powerful in
demonstrating what is happening in an enterprise. However, they did not address how
virtual worlds can be used as an alternative tool for facilitating communication in
business process modeling tasks, in particular, how human resource models relate to
process models.
3
3.1
      </p>
    </sec>
    <sec id="sec-3">
      <title>Virtual World as the Model-View Communication Approach</title>
      <sec id="sec-3-1">
        <title>Business Improvement and Optimization Activity Review</title>
        <p>
          At the operational level, people are interested in the specific sequence of task events,
personnel arrangement and resource behavior [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ]. To satisfy these interests, we
believe the following list of visualization aspects (but not limited to) should be
addressed: Physical Environment and Human Resource Behavior, Entity
Representation, Information Display, Business Scenario Rehearsals. These are diagrammatically
represented as supporting points in the improvement process life cycle shown in
Fig.3.
 Physical Environment and Human Resource Behavior --- The states of a physical
environment impacts the behavior of a human resource and business task transition
[
          <xref ref-type="bibr" rid="ref16">16</xref>
          ]. Visualization of this aspect enables insight into relationships between a
physical environment and business processes.
 Entity Representation --- Business analysts usually use simple 2D objects to
abstractly represent real objects. For example, process models grammars, such as
BPMN, are used to describe the state transition of tasks, ER diagram are used to
reflect the relationship between human resources and non-human resources.
 Information Display --- Information may be loosely classified as qualitative and
quantitative information. Representations of this information will provide people
with insight into the workload of human resources, and utilization rates of
nonhuman resources.
 Business Scenario Rehearsals --- Sometimes, business analysts need to use simple
visual approaches, such as sliders, to demonstrate the consequence of enacted
business models [
          <xref ref-type="bibr" rid="ref17">17</xref>
          ]. Such visual assistance is an essential approach in
requirements elicitation and analysis.
3.2
        </p>
      </sec>
      <sec id="sec-3-2">
        <title>Virtual World Introduction</title>
        <p>
          A virtual world is a network-based, computer synthesized dynamic environment,
where participants can communicate with each other and observe computer-generated
environmental objects [
          <xref ref-type="bibr" rid="ref18">18</xref>
          ]. Some selected features are discussed below:
 Geometry Representation. The geometry in a virtual world is composed of a
metadata called geometric meshes. The combination of geometric meshes can form the
shape of real objects.
 Programming. People can use programming languages to implement system
functions, such as the reaction of an object based upon the current state of the virtual
world and database connections and/or document printing.
 Avatars. An avatar is a 3D graphical representation of a virtual world participant
with a humanoid appearance, it can be used as a vehicle for virtual world creation,
exploration and modification, or for presenting an artificial agent.
 Behavior Modeling. A behavioral model is the mathematical formulae of the
movement logic implemented by a programming language. Examples of a behavior
model can be a picking up goods from the table of an avatar receiving an order.
 Information Visualization, depending on the analysis task, information can be
represented in 3D, or can be represented via a 2D representation on a Heads Up
Display (HUD).
3.3
        </p>
      </sec>
      <sec id="sec-3-3">
        <title>Virtual World As Alternative Communication Approach in Business</title>
      </sec>
      <sec id="sec-3-4">
        <title>Process Improvement</title>
        <p>We now explore the rationale behind using a virtual world as a communication
approach in business process modeling. An overview of how the virtual world can
satisfy visualization needs during the communication process is described in Table.1.</p>
        <p>Thus, synthetic environments and observable inhabitants of a virtual world, if being
correctly translated from reality, enable business analysts and stakeholders to have a
concrete observable instance as an object to assess, evaluate, predicate and identify.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Case Study</title>
      <sec id="sec-4-1">
        <title>Visualization Applications</title>
        <p>
          We utilized the YAWL system [
          <xref ref-type="bibr" rid="ref21">21</xref>
          ], JADE1, OpenSim2, Hippo OpenSim Viewer3 and
OpenMetaverse4 API to implement our prototype as a proof of concept. The YAWL
1 jade.tilab.com
2 www.opensimulator.org
system is a WfMS that employs a workflow language called YAWL (Yet Another
Workflow Language) [
          <xref ref-type="bibr" rid="ref22">22</xref>
          ]. JADE (Java Agent DEvelopment Framework) is a JAVA
based agent platform, providing developers with an agent system infrastructure
platform. These two packages are used to implement our previous agent system [
          <xref ref-type="bibr" rid="ref23">23</xref>
          ] that
provides underlying agent behaviors, with reference to workflow activity allocation
commands. OpenSim, Hippo OpenSim Viewer and OpenMetaverse are 3D
application server, 3D application client, and API for behavior modeling of human resource.
These three API packages are used to implement our prototype visualization system
on top of the agent infrastructure, to produce the images seen in this paper. The
architecture of our system is available in Fig.5. We illustrate this architecture with
modelview-control (MVC) design pattern.
        </p>
      </sec>
      <sec id="sec-4-2">
        <title>Application in Conceptual Modeling and Modeling Validation.</title>
        <p>In a virtual world, people can work together to discuss conceptual models in a
direct manner. They can create geometries attached with different textures representing
the artifacts used in the reality, and juxtapose these geometries with a modified form
of conceptual model. Due to the ability to see the conceptual model in the same space
as the person’s workplace, business analysts can easily sketch up the components of a
model, see Fig.6, and then display them to stakeholders, who can confirm validity of
the model.
3 www.mjm-labs.com/viewer
4 www.openmetaverse.org</p>
      </sec>
      <sec id="sec-4-3">
        <title>Application in Business Process Simulation.</title>
        <p>In a virtual world, the actual human resource performance and corresponding
abstracted information can be simultaneously observed. For example, the concrete and
abstract information of task blood transfusion are available to participants, see Fig.9.
A local view toward this task such as the responsibility of human resource and
nonhuman resource utilization (the blood bag) can be obtained by native stakeholders.
The abstracted information, such as the temporal ordering of task and entity
relationship, can be represented through a process model in the HUD (Image D, Fig. 7).
The main purpose of this paper is to provide a visualization approach to strengthen
the communication channels between business analysts and stakeholders, before any
improvement and optimization activity is conducted. Based on this research, one
possible direction forward is the visualization of deviations between two conceptual
models that need to be considered. Currently, our system can visualize a workflow
system with different simulation configurations by converting the “as-is” result in to
3D visualization of the “to-be”. An intuitive indication is still needed for native
stakeholders to understand the changes to be introduced by the new model.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Acknowledgement</title>
      <p>This research has been financially supported by the Smart Services CRC in Australia
http://www.smartservicescrc.com.au.</p>
    </sec>
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