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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>On the Performance Prediction Capabilities of the eBPMN-based Model-driven Method for Business Process Simulation</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Enterprise Engineering University of Rome Tor Vergata Via del Politecnico 1 00133</institution>
          ,
          <addr-line>Rome</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Guglielmo Marconi University Dept. of Innovation and Information Engineering Via Plinio 44 00193</institution>
          ,
          <addr-line>Rome</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>-The analysis of business processes may take considerable advantage by the adoption of simulation-based techniques from the early phases of process lifecycle. Despite the fact that Modeling &amp; Simulation (M&amp;S) approaches have been widely recognized as a valuable solution, the remarkable effort required for their implementation and their essential complexity may limit their use in practice. In previous contributions we have proposed a model-driven method and a domain specific language, named eBPMN, for enabling the automated development and execution of business process simulations. In this paper, we analyze the performance prediction capabilities of the current implementation of the eBPMN-based model-driven method, by means of a comparison with the same capabilities provided by similar existing tools, such as BIMP and Bizagi, for a reference business process. Index Terms-Business Process Model and Notation (BPMN), Business Process Management, Modeling and Simulation, Business Process Analysis</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Copyright c held by the author</title>
    </sec>
    <sec id="sec-2">
      <title>I. INTRODUCTION</title>
      <p>Modern organizations have to face a constantly evolving
market, characterized by rapidly changing demands and
increasing levels of competition. In such a context, it becomes
crucial for organizations to get a deep knowledge of their
operational business model and thus have the ability to
dynamically improve it, in order to gain a competitive advantage
and better exploit market opportunities. Specifically, a deep
understanding of the operational business processes is essential
to enhance organization efficiency and improve the quality of
delivered products and/or provided services.</p>
      <p>
        As a consequence, the vast majority of organizations have
embraced Business Process Management (BPM) approaches,
which include methods, techniques, and tools to support the
design, analysis, enactment and improvement of operational
business processes [
        <xref ref-type="bibr" rid="ref42">42</xref>
        ]. A business process (BP) can be
defined as a set of interrelated activities that are executed
by one or more organizations working together to achieve a
common business purpose [
        <xref ref-type="bibr" rid="ref31">31</xref>
        ], [
        <xref ref-type="bibr" rid="ref25">25</xref>
        ].
      </p>
      <p>
        From an operational perspective, several modeling
languages have been introduced in the last years to specify
business processes. Among them, the Business Process Model
and Notation (BPMN) [
        <xref ref-type="bibr" rid="ref34">34</xref>
        ], provided by OMG, is playing a
primary role as the de facto standard in the BPM domain.
BPMN is widely adopted by users with different backgrounds
and roles, ranging from business analysts to IT experts [
        <xref ref-type="bibr" rid="ref32">32</xref>
        ].
      </p>
      <p>Since the complexity of modern BPs is constantly
increasing, it becomes essential to use innovative methodologies and
techniques to effectively support BP analysis activities right
from the first phases of the BP lifecycle.</p>
      <sec id="sec-2-1">
        <title>In this respect, the use of Modeling and Simulation (M&amp;S)</title>
        <p>
          techniques has been identified as an effective BP analysis
approach [
          <xref ref-type="bibr" rid="ref43">43</xref>
          ], providing a valid support at both design time
and operations time.
        </p>
        <p>
          Although M&amp;S approaches are widely recognized as
extremely valuable [
          <xref ref-type="bibr" rid="ref20">20</xref>
          ], their practical use is not yet widespread
as one would expect, due to two main factors. On the one
hand, the cost to set up and to maintain a M&amp;S environment
is often not-negligible. On the other hand, the use of
M&amp;Sbased techniques requires skills and know-how which most
business analysts are not familiar with.
        </p>
        <p>
          In previous contributions, we have introduced a framework
that largely reduces the effort and the cost for carrying out
simulation-based BP analysis activity. The proposed
framework exploits standards and technologies introduced in the
model-driven development field to ease and automate the
simulation-based BP analysis [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ]. The framework introduces
a domain-specific language, named eBPMN, for the
specification and execution of BP simulation models.
        </p>
        <p>eBPMN allows one to carry out BP analysis activities by
addressing both performance (i.e., efficiency) and reliability
(i.e., failure-free behavior) properties. This paper specifically
focuses on the performance prediction capabilities of the
current implementation of eBPMN. The paper discusses the
effectiveness and validity of such predictions by means of a
comparison between the key performance indicators and the
results provided by eBPMN and those provided by other
wellknow and widely used tools, such as BIMP and Bizagi, for a
reference business process.</p>
        <p>The comparison allows us to conclude that eBPMN enables
business analysts to get the same performance predictions of
commonly available BP simulation tools, with the additional
advantages of:
not requiring the manual specification and/or
implementation of the simulation model, which can be automatically
generated from BP models specified by use of BPMN or
other BP modeling languages;
providing both sequential and distributed simulation
execution engines, which can be easily integrated into MSaaS
(M&amp;S as a Service) platforms.</p>
        <p>The rest of this paper is organized as follows: Section II
provides the necessary background and discusses related works.
Section III outiles the aforementioned features of eBPMN
and illustrates the comparison approach, while Section IV
introduces the case study that has been used as a reference
scenario for BP performance analysis. Section V discusses the
related results and, finally, Section VI gives final remarks.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>II. BACKGROUND</title>
      <p>
        The reasons for adopting simulation techniques in the BPM
domain have been investigated in [
        <xref ref-type="bibr" rid="ref38">38</xref>
        ], [
        <xref ref-type="bibr" rid="ref37">37</xref>
        ]. Typically,
simulation techniques can answer questions such as [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ], [
        <xref ref-type="bibr" rid="ref26">26</xref>
        ]: what
are the total process time and the maximum throughput of the
process, what are the equipment and technology requirements
to meet the service demand, what are the waiting times, what
is the best assignment of resources to task and how to deal
with unexpected situations or emergencies.
      </p>
      <p>
        However, the potential of M&amp;S approaches is not fully
exploited yet, mainly due to the fact that the several
existing simulation tools require conceptual and technical skills
beyond those generally available in business organizations
[
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. In this regard, a survey conducted among potential BP
simulation users reveals that almost 80% of respondents do not
use simulation techniques, while actual users report as main
motivations the ability of simulation-based analysis to support
extensive experimentation and get a deeper understanding of
complex process interactions [
        <xref ref-type="bibr" rid="ref33">33</xref>
        ].
      </p>
      <p>
        A systematic review of business process simulation tools
can be found in [
        <xref ref-type="bibr" rid="ref29">29</xref>
        ], in which the authors evaluate their
applicability, underline some limitations and derive
recommendations for further research. The review analyzes business
process modeling tools that may be applicable for simulation
(e.g., Protos, ARIS), tools that expose simulation capabilities
(e.g., FLOWer, FileNet) and general purpose simulation tools
(e.g., Arena, Colored Petri-Net tools). The evaluation is based
on modeling capabilities (ease of model building, formal
semantics and verification of correctness, workflow patterns,
resource and data perspective, level of detail, transparency
and suitability for communication), simulation capabilities
(performance dimensions, distributions, animation, scenarios)
and output analysis capabilities (statistics, format, what-if
analysis, decision-making support).
      </p>
      <p>
        An updated review on the role of simulation techniques
can be found in [
        <xref ref-type="bibr" rid="ref28">28</xref>
        ], in which authors report that
discreteevent simulation is by far the most investigated technique
(about 40% of the literature contributions), followed by system
dynamics (about 15%), hybrid techniques and Monte-Carlo
simulation, among the others.
      </p>
      <p>
        An additional comparison of BP simulation tools is
described in [
        <xref ref-type="bibr" rid="ref27">27</xref>
        ], in which authors classify the reviewed tools
(e.g., JBoss jBPM simulation tool, Oracle Business
Process Analysis Suite, SigmaFlow modeler, Arena simulation
modeling tool) in terms of licensing options and addressed
application domains.
      </p>
      <p>Beyond the various features and capabilities of the several
BP simulation tools reviewed in the aforementioned
contributions, what is considered as an actual impediment to the
effective use of M&amp;S-based approaches in the BPM domain
is the semantic gap that often exists between the BP-based
conceptual model and the BP simulation model.</p>
      <p>
        From a practical perspective, in [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ] the authors observe
that a main focus of research is to provide simulation building
blocks that are as close as possible to the elements of the
conceptual model. The authors point out that a slight difference
between the conceptual model and the simulation language
can lead to difficulties in translating the model and, in some
cases, to the impossibility to carry out such translation. In this
respect, in [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] the author argues that most of the currently
available simulation tools provide hard-coded simulation
capabilities, failing to explicitly define the underlying simulation
modeling formalism by use of, e.g., a well defined metamodel.
      </p>
      <p>
        Attempts to bridge the gap between conceptual and
simulation models are documented in [
        <xref ref-type="bibr" rid="ref40">40</xref>
        ], [
        <xref ref-type="bibr" rid="ref30">30</xref>
        ], [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ], [
        <xref ref-type="bibr" rid="ref39">39</xref>
        ]. Such
attempts are based either on the provision of specific simulation
languages, such as the event-driven Simulation Activity
Diagram (SAD) language introduced in [
        <xref ref-type="bibr" rid="ref40">40</xref>
        ], or on more flexible
and effective approaches based on model-driven development
and automated model transformations, such as in [
        <xref ref-type="bibr" rid="ref30">30</xref>
        ], which
proposes a model transformation approach that can be used to
translate conceptual process models, expressed in the
eventdriven process chain (EPC) notation, to different simulation
software systems, and in [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ], which presents a framework
that exploits metamodeling and model transformations in order
to translate conceptual elements into executable simulation
components. Similarly, in [
        <xref ref-type="bibr" rid="ref39">39</xref>
        ] a model-driven approach is
used to transform BPMN models into DEVS models and
then to Java classes used for the simulation with the DSOL
(Distributed Simulation Object Library) library.
      </p>
      <p>To summarize, the analysis of the literature reveals a
considerably wide offer of M&amp;S tools for BP simulation, but still
a limited use of the potential offered by M&amp;S approaches for
BP analysis. Further, several existing simulation tools require
specific know-how in M&amp;S, as well as software engineering
skills, far beyond those generally available in business
organizations. As such, model-driven development can be considered
one of the most effective approaches to provide the required
degree of automation, which helps to reduce the effort and
cost of M&amp;S-based BP analysis.</p>
      <p>
        In this respect, we have proposed a full featured
modeldriven framework that introduces a set of automated model
transformations to translate BP models into corresponding
BP simulation models and simulation model implementations
ready to be executed on top of sequential or distributed
simulation engines [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ], [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. The framework includes a
domainspecific language, named eBPMN, to specify and execute BP
simulation models automatically generated from BP models
specified in a given BP modeling language, such as BPMN or
UML.
      </p>
      <p>III. THE EBPMN DOMAIN-SPECIFIC LANGUAGE
FOR BP SIMULATION
number of tokens processed by each element and by each
resource as a measure of the throughput;
tokens managed on each branch of gateways as a measure
of the usage of each possible business process flow;
cycle time (mean and variance) as the time spent by a
token to complete the collaboration from token generation
at start node to token termination at end node.</p>
      <p>
        Although eBPMN allows to simulate both the performance
and the reliability behavior of the business process [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ], in this
paper we specifically focus on performance properties. This
is due to the fact that the proposed approach for performance
prediction analysis is based on comparing the eBPMN results
with those obtained with other existing BPMN simulators
which do not provide process reliability simulation.
      </p>
      <sec id="sec-3-1">
        <title>B. eBPMN-based Model-Driven Method</title>
      </sec>
      <sec id="sec-3-2">
        <title>A. eBPMN Overview</title>
        <p>
          One of the main advantages of eBPMN is that the executable
code can be directly obtained in an automated fashion from
standard BPMN models by use of a model-driven method
based on automated model transformations [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ], [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ].
        </p>
        <p>
          As aforementioned, such transformations rely on a
lightweight extension of the BPMN metamodel, named
PyBPMN, that has been defined in previous works [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ] as a
semantics preserving extension that does not alter the original
BPMN metamodel. PyBPMN gives the ability to annotate
standard BPMN models with performance-oriented BP
properties. The annotated BPMN model is then directly mapped to
eBPMN executable code.
        </p>
        <p>
          The PyBPMN metamodel introduces specific metaclasses
for the following components:
eBPMN is a domain-specific simulation language based on
the execution semantics defined in the BPMN 2.0 specification
[
          <xref ref-type="bibr" rid="ref34">34</xref>
          ]. It has been originally introduced in [
          <xref ref-type="bibr" rid="ref12">12</xref>
          ] and further
extended in [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ], [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ], [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ], [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ].
        </p>
        <p>
          The eBPMN language has been built on top of SimArch
[
          <xref ref-type="bibr" rid="ref21">21</xref>
          ], a layered software architecture which gives users the
ability to specify event-driven simulation models that can be
transparently executed either in local or distributed simulation
environments. A detailed description of SimArch is given in
[
          <xref ref-type="bibr" rid="ref22">22</xref>
          ].
        </p>
        <p>
          eBPMN allows users to simulate BPs consisting of a single
participant as well as complex process collaborations. A BP
element (task or activity) makes use of a single resource workload definition: responsible for modeling the
workor more resources to perform its job. In order to specify load related to the whole business process or to the tasks
the resources behavior and the non-functional properties of associated to the process (i.e., the execution of single
BPMN elements, eBPMN exploits a lightweight BPMN exten- activities);
sion named PyBPMN (Performability-enabled BPMN), briefly performance properties definition: responsible for
specisummarized in next sub-section and detailed in [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ]. fying the performance properties associated to both the
        </p>
        <p>The eBPMN language implements a token abstraction to process and the single task. The most common
perforsimulate the execution of a BPMN process. A token is gener- mance properties are the service demand (service time),
ated by a Start node and can be considered as a reference the time spent to accomplish the demand (response time),
to the execution of a process instance. The time interval and the throughput;
between two subsequent token generation events follows a reliability properties definition: responsible for modeling
given probability distribution. After creation, the token goes the reliability related properties of the resources involved
throughout the process nodes, guided by the sequence flows, in a process or associated with a task. The most common
and each eBPMN element handles the token according to its reliability properties are the occurrence rate of the failure,
execution semantics. At the End node the token is destroyed the occurrence distribution of the failure, the mean time
and the simulation environment gathers information about the to failure (MTTF) and the mean time to repair (MTTR);
process traversal. resource management: responsible for specifying the</p>
        <p>
          The eBPMN simulation language provides the following actual resource which is used to execute an activity.
performance metrics for process elements and collaborations: PyBPMN allows to define non functional properties for
service time (mean and variance) and waiting time (mean atomic resources, as well as groups of resources
consistand variance) for resources and tasks; ing of concurrent or alternative resources.
resource utilization, i.e., the time spent by a resource The eBPMN-based model-driven method has been
specin executing service requests, considering the amount ified using languages and tools introduced by the OMG’s
of parallel working units and thus evaluating bottleneck MDA (Model Driven Architecture) incarnation of
modelissues; driven development principles, and implemented within the
Eclipse Modeling Framework (EMF) platform [
          <xref ref-type="bibr" rid="ref18">18</xref>
          ], [
          <xref ref-type="bibr" rid="ref41">41</xref>
          ] and
the Eclipse Modeling Project [
          <xref ref-type="bibr" rid="ref19">19</xref>
          ], [
          <xref ref-type="bibr" rid="ref24">24</xref>
          ]. The following Eclipse
plugins have been implemented in order to provide a tool-chain
that eases the production of the eBPMN-based simulation code
from a standard BPMN model:
a plugin implementing the PyBPMN metamodel;
a plugin implementing the BPMN to PyBPMN
model-tomodel transformation;
a plugin implementing the PyBPMN to eBPMN
modelto-text transformation.
        </p>
        <p>
          The tool-chain is being ported and deployed into
cloudbased environments, according to the MSaaS paradigm. The
proposed MSaaS platforms includes the aforementioned model
transformation services, a SimArch-based simulation execution
engine, which allows users to execute eBPMN simulations on
top of either sequential or distributed simulation environments,
and modeling services to directly specify eBPMN simulation
models, as described in [
          <xref ref-type="bibr" rid="ref11">11</xref>
          ], [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ], [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ].
        </p>
      </sec>
      <sec id="sec-3-3">
        <title>C. eBPMN Performance Prediction</title>
        <p>
          In order to analyze the eBPMN performance prediction
capabilities, an indirect approach has been adopted. The
analysis is carried out by comparing the results provided by
eBPMN with the outputs provided, for the same process and
input parameters, by two well-known tools that offer similar
features, i.e., Bizagi Process Modeler [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ] and BIMP [
          <xref ref-type="bibr" rid="ref3">3</xref>
          ].
        </p>
        <p>
          The Bizagi Process Modeler (Bizagi in short) is a business
process modeling and documentation tool, compliant with
the BPMN 2.0 specification, that allows to visualize, model
and document business processes using BPMN. The Bizagi
Process Modeler also provides simulation parameterization
capabilities that conform to the BPSim specification [
          <xref ref-type="bibr" rid="ref44">44</xref>
          ].
        </p>
        <p>BIMP is a simulator of business process models, free for
academic use, available either through a web-based interface
or according to a simulation as a service paradigm.</p>
        <p>The comparison is carried out with respect to some specific
performance measures, or Key Performance Indicators (KPIs),
which are able to capture the essential aspects of the business
process performance behavior.</p>
        <p>
          In this respect, a significant effort has been spent in order
to deal with the definition of appropriate KPIs for BPM
[
          <xref ref-type="bibr" rid="ref13">13</xref>
          ], [
          <xref ref-type="bibr" rid="ref35">35</xref>
          ], [
          <xref ref-type="bibr" rid="ref36">36</xref>
          ]. A typical performance metric of interest for
business processes is the cycle time, i.e., the time taken to
handle one token (one process instance), addressed in terms of
maximum value, average value or its variation over instances.
Further, cycle time can be analyzed through its constituent
measures such as the service time (the time spent to actually
handling the token) or the waiting time (the time spent in idle
mode, either in queue or waiting for synchronization) [
          <xref ref-type="bibr" rid="ref17">17</xref>
          ].
        </p>
        <p>For the comparison of results provided by eBPMN, BIMP
and Bizagi, the following KPIs have been taken into
consideration:
process cycle time;
resource utilization;
activity waiting time.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>IV. CASE STUDY FOR PERFORMANCE</title>
      <p>VALIDATION</p>
      <p>The process considered for eBPMN validation is a health
care process, specifically a process dealing with diabetes
care. Diabetes of type 1 must be treated with medicines
throughout life. Affected patients should take insulin to avoid
excessive glycemic peaks. Pharmacological treatment aims at
controlling the symptoms of diabetes and preventing serious
complications.</p>
      <p>The case study refers to the request of essential products
for diabetes care. The start event consists of the expiration
of the periodic treatment of a patient, which results in the
need to contact the salesman to acquire new medicines. The
salesman, following the patient necessary quantities, prepares
a new medicines plan, which has then to be approved by
the reference doctor (i.e., the diabetologist). After the plan
approval, the salesman forwards the order to the
pharmaceutical industry that packages the medicines. The pharmaceutical
industry then sends the medicines to the main hospital, which
locates the authorized medical center closest to the patient
facility and forwards the medicines to it. Finally, the medical
center notifies the patient of the availability of the requested
medicines and the process ends. Both the medicines plan and
the order can be subjected to refusal (with a 15% probability),
which leads to rework of the request.</p>
      <p>The BPMN model of the reference process is depicted in
Figure 1.</p>
      <p>Each pool in the BPMN model defines a resource role
involved in the process. Each role is associated with one
or more actual resources (performers) which are able to
execute the activity. Table I summarizes the resources roles
and the corresponding amount of performers considered for
the reference process.</p>
      <p>For each activity in the process, Table II reports both the
average service time and the resource performing the activity.</p>
    </sec>
    <sec id="sec-5">
      <title>V. RESULTS</title>
      <p>The performance validation has been carried out simulating
the reference process with respect to two different scenarios
A and B, which differ for the expected workload in terms
of patients requests average inter-arrival time: 4 hours for
scenario A and 3 hours for scenario B. Thus, scenario B deals
with a more intensive workload.</p>
      <p>The simulation has been set-up considering exponential
probability distributions for inter-arrival and activity times.</p>
      <p>As for the simulation duration, both eBPMN and Bizagi
allow to stop the simulation after a given simulated time, while
BIMP simulations are stopped when all the tokens generated
by start nodes are terminated at the end nodes. The use of
probability distributions for inter-arrival time, activities
duration and gateways routing policies introduces some uncertainty
on precision of the provided results. Indeed, if the termination
condition is the maximum simulated time, the exact number
of processed tokens is not exactly predictable; on the other
end, if the termination condition is the number of tokens, the
actual simulated time is not exactly predictable.</p>
      <p>However, if the simulated time is long enough, all the results
tend towards the steady-state conditions of the process. This
allows to compare the results of different tools even if they
have simulated a different amount of process instances.</p>
      <p>For the purpose of this paper, the simulation stops after 365
simulated days for eBPMN and Bizagi (about 2000 tokens
processed per run) and after 3000 tokens for BIMP (to meet
tool constraints on simulation duration). Further, eBPMN and
Bizagi automatically execute 50 runs of the process to reduce
statistical error. BIMP does not allow to specify the number
of runs so the simulation has been manually re-run to evaluate
average values.</p>
      <p>The aforementioned quantities have been chosen as a
reasonable trade-off between minimizing the statistical error
and limiting the simulation complexity (eBPMN and Bizagi
provide results in about 2 minutes on a typical desktop PC
with 4th-generation Intel i5 CPU and 8 GByte of RAM).</p>
      <p>Moreover, it should be noted that eBPMN and Bizagi
provide repeatable deterministic simulations while BIMP does
not, so repeating the BIMP simulation could lead to different
values.</p>
      <p>The KPIs provided by eBPMN, BIMP and Bizagi for
scenario A are depicted in Figure 2, while Figure 3 presents the
same KPIs for scenario B. Corresponding figures use the same
scale to make easier the comparison of the KPI on workload
variation.</p>
      <p>The simulation of the two scenarios shows comparable
performance predictions of process times, resources utilization
and waiting times for eBPMN, BIMP and Bizagi. Differences
in some values are likely due to pseudo-random number
generation for probability distribution approximation.</p>
      <p>As expected, increasing the workload (i.e., switching from
scenario A to scenario B) leads to higher resource
utilization. The pharmaceutical industry has the highest utilization
(from 60% for scenario A to 80% for scenario B). Under
these conditions, the resource is working near its maximum
capacity and the waiting times for activities performed by such
16 18 20 22 24</p>
      <p>Average cycle time [h]
eBPMN</p>
    </sec>
    <sec id="sec-6">
      <title>BIMP Bizagi</title>
      <p>eBPMN</p>
    </sec>
    <sec id="sec-7">
      <title>BIMP Bizagi</title>
      <p>resource quickly go up. This behavior is captured, with minor
differences, by all the considered tools (for the Check order
activity eBPMN shows higher waiting times than the other
two tools, while for Prepare medicines and Send medicines to
hospital Bizagi predicts lower waiting times than eBPMN and
BIMP).</p>
    </sec>
    <sec id="sec-8">
      <title>VI. CONCLUSIONS</title>
      <p>The paper presents an analysis of the performance
prediction capabilities for the current implementation of eBPMN,
a domain-specific simulation language for BP simulation.
The main advantages of eBPMN is its formal specification,
compliant with the execution semantic of BPMN, and the
ability to automatically generate the eBPMN executable code
applying a model-driven tool-chain to the BPMN model.</p>
      <p>The analysis of the BP performance prediction has been
carried out by comparing the results of eBPMN with those
provided by similar tools, i.e., BIMP and Bizagi Process
Modeler, for a reference BP. The validation procedure has
been applied to two scenarios for the reference process with
different workload characterization. The analysis of the
results reveals comparable performance predictions for eBPMN,
BIMP and Bizagi for cycle time, resource utilization and
waiting times.</p>
      <p>The comparison has showed that eBPMN enables business
analysts to get the same performance predictions of similar
BP simulation tools, with the additional advantages of not
requiring the manual specification and/or implementation of
the simulation model, which can be automatically generated
from BP models specified by use of BPMN or other BP
modeling languages, and using a sequential/distributed simulation
execution engine, which can be easily integrated into MSaaS
(M&amp;S as a Service) platforms.
0
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
32
34
36
38
40</p>
    </sec>
    <sec id="sec-9">
      <title>Average cycle time [h]</title>
      <p>eBPMN
eBPMN</p>
    </sec>
    <sec id="sec-10">
      <title>BIMP Bizagi</title>
    </sec>
  </body>
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