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    <article-meta>
      <title-group>
        <article-title>Bringing Model-based Systems Engineering Capabilities to Project Management: an Application to PRINCE2</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Diana Coppola</string-name>
          <email>dianacoppola@virgilio.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Andrea D'Ambrogio</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Daniele Gianni</string-name>
          <email>d.gianni@unimarconi.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Dept. of Applied Sciences and Technologies Guglielmo Marconi University Rome</institution>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>-PRINCE2 is arguably one of the most adopted process-based methods for project management. Currently, PRINCE2 is defined in a textual specification, which describes the principles, the themes, and the processes that project managers should apply in their management activities. Although the specification is well structured and mature, the specification does not provide a browsable digital representation that can be interactively used for learning and/or for the specification application during project management activities. This paper aims to overcome these limitations with the application of a modelbased systems engineering approach to represent the PRINCE2 specification in a model-based format. This can bring several benefits to the specification, including the availability of a graphical, comprehensive and digitally browsable visualization of the PRINCE2 processes, their inputs/outputs, and the constituting tasks. The modelbased format has been obtained by a top-down mapping of the PRINCE2 specifications, beginning with the process architecture in IDEF0 down to the individual tasks, roles, and tools in BPMN 2.0. Besides supporting PRINCE2 understanding and application, the model-based format can also serve as a baseline for further exploitations, such as consistency verification of the PRINCE2 specification and model-based process simulation for the governance of the PRINCE2 processes and of the project management activities.</p>
      </abstract>
      <kwd-group>
        <kwd>project management</kwd>
        <kwd>business process</kwd>
        <kwd>model-based</kwd>
        <kwd>systems engineering</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>Copyright © held by the author.</p>
      <p>INTRODUCTION</p>
      <p>
        Project management methodologies have been
increasingly adopted to structure, monitor, control, and
execute temporary and cross-functional organizational
activities in order to support managers with the
information, tools, and processes to increase
predictability in the delivery of the expected output.
These methodologies have also been shown to increase
the overall efficiency in terms of resource optimization,
risk management, and cost management [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. More
tangibly, in the last decades, several studies have
provided evidence about the link between the enterprise
2 Dept. of Enterprise Engineering
University of Rome Tor Vergata
      </p>
      <p>
        Rome, Italy
dambro@uniroma2.it
performance indicators and the maturity level of the
adopted project management methodology [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ].
      </p>
      <p>PRINCE2 is arguably one of the most adopted
standard project management methodologies in various
systems engineering domains. PRINCE2 has been more
and more adopted since 2009, for three reasons:
1. the overall trend of business to use a
projectbased approach to develop products or
transformations within increasingly collaborative
contexts with multiple partners;
2. the overall trend of capitalizing on knowledge of
best practices in project management;
3. the inherent PRINCE2 characteristics, such as the
general approach (i.e. application/domain
independent), the product-based planning or the
product breakdown structuring.</p>
      <p>
        However, PRINCE2 is still relatively complex to learn
and to apply as the specification sequentially presents all
the PRINCE2 elements (particularly the processes),
which are highly interleaved during a PRINCE2 project
execution. As a consequence, the project manager is
required to build a detailed mental map of the
interconnections to directly access the relevant parts of
the specifications. Expert project managers, who have
been using PRINCE2 for ten or more years, have likely
mastered all these interconnections. However, younger
and aspiring project managers may require more
assistance and time to become fully familiar with these
interconnections. In the wider systems engineering
community, model-based approaches have often been
introduced to represent document-based specifications
with the implicit objectives of providing an automated
processing, a direct (i.e. non linear access to the
individual parts), and an integration with other
supporting tools for decision making [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ].
      </p>
      <p>In this paper, we apply a model-based systems
engineering approach to the representation of PRINCE2
in order to facilitate the communication, the
understanding, and the application of the PRINCE2
method. Our model-based approach consists of: IDEF0
diagrams for the representation of the PRINCE2 process
architecture; BPMN diagrams for the detailed
description of the PRINCE2 processes; a set of
supporting tables to further assist the project manager in
reading the model and in following the development of
the project in PRINCE2.</p>
      <p>The paper is structured as follows. The background
section provides the fundamental terminology used in
PRINCE2 and in business process modeling. The related
work section positions this paper’s contribution with
respect to the state-of-art. The method section illustrates
and motivates the model organization, from the
architecture to the details of PRINCE2. Finally, the
conclusion section provides closing remarks and
directions for further developments.</p>
      <p>II.</p>
      <p>BACKGROUND</p>
      <p>This section briefly recalls the main concepts
introduced by project management methodologies (i.e.,
PRINCE2), modeling methodologies (i.e., IDEF0) and
modeling languages (i.e., BPMN).</p>
    </sec>
    <sec id="sec-2">
      <title>A. PRINCE2</title>
      <p>
        PRINCE2 has been introduced in 2006 by the UK’s
Department of Commerce, and is now developed by
AXELOS [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. PRINCE2 is a best practice for the
organization, management, and control of projects of
any size within any organizational context. Although
PRINCE2 is of general purpose application, it is based
on a structured method which guides the project
manager in the application of the best practices for the
project definition and execution. As further advantages,
PRINCE2 offers means to standardize the
communication among the actors, to focus on the
product to be delivered, and to ensure responsibilities
assignment to the actors, and also to embed agile
approaches within the PRINCE2 specification.
      </p>
      <p>PRINCE2 consists of the following elements: seven
principles—which define the fundamental rules satisfied
by the following elements; seven themes—which define
the areas of concerns in a project; and seven inter-linked
processes—which define the activities to be performed
during the project life-cycle, seven themes, and seven
processes; nine roles (e.g. project manager, supplier,
customer, executive, team, etc.)—which define the
responsibilities in the project; and 26 internal project
products (business case, project plan, risk register,
etc.)—which inherently define the dependencies among
the processes. Fig. 1 shows the seven processes along
the four stages of a PRINCE2 process and the three
levels of actions (directing, managing, executing).</p>
      <p>The Pre-project phase regards the preliminary
evaluation of the validity and the convenience of project.
In this phase, the process SU develops two key
documents: Project Brief and Plan for the Beginning of
the Project. These documents are taken as input by the
process DP, in which the project board assesses the plan
to decide whether or not to authorize the project. In the
positive case, the project execution moves to the
Initiation stage phase, in which the processes IP and SB
are implemented. The former produces several internal
project documents, such as detailed business cases (from
the initial project brief) and guidelines to assess the
achievement of the expected benefits. Differently, the
process SB produces a detailed planning for the
execution of the following stage.</p>
      <p>
        IDEF refers to a family of modeling methodologies
widely adopted in the field of systems and software
engineering [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. Specifically, IDEF0 is a function
modeling methodology for describing manufacturing
functions. IDEF0 provides a functional modeling
language consisting of three elements:
1. Diagrams, which represent the structure of the
process architecture in terms of activities (boxes)
and their dependencies (arrows).
2. Text, which are labels that can provide further
information on the elements in a diagram (e.g.
name of the activity, etc.).
3. Glossary, which define extensively all the labels,
names, and acronyms defined in the diagrams.
      </p>
      <p>However, IDEF0 also allows the use of
supplementary material, also known as FEO (For
Exposition Only) pages, which can be used to
represent flow diagrams or technical design using any
formalism.</p>
      <p>Graphically, a diagram consists of a frame, and one
or more boxes and arrows. Asides from delimiting the
area for the drawing of boxes and arrows, the frame
provides also a preassigned location for the diagram
name. For the top-level (or context) diagram defining
the overall process, the name must be “A-0”. This
diagram “declares” the process and also indicates the
parameters related to the model purpose and scope,
which are needed to check the consistency and
appropriateness of child diagrams. The first child
diagram must be named “A0” and defines the
composition of overall process. This diagram must
contain between 3 and 6 activities, which boxes are to
be located on the upper-left/lower-right diagonal of the
diagram’s frame, following a temporal order in the
development of the activities. Further child diagrams
can be introduced by recursively detailing an activity
already defined in one diagram. For each child
diagram, a DRE (Detail Reference Expression) is to be
used as part of a diagram name to link the diagrams.
This expression corresponds to the unique and
hierarchically-structured numeric identifier placed at
the bottom-right corner of the box representing the
activity. Concerning the arrows, these can be used to
represent dependencies of input/output, on external
conditions, or on resources. Graphically, these
dependencies lead to the following type of arrows
(Fig.2):
• Input: incoming arrow into the left side of the box.</p>
      <p>This arrow represents data or objects that are
transformed by the activity;
• Output: outgoing arrow from the right side. This
arrow represents the output produced by the activity.
• Controls (or Constraints): incoming arrow from the
top of the box. This arrow represents external
conditions (e.g. norms, procedures, regulations, etc.)
that are required for the activity to be successfully
developed.
• Mechanisms (or Resources): incoming arrow from
the bottom of the box. This arrow represents the
means or resources (machinery, information
systems, humar resources, etc.) needed to perform
the activity.
• Recall (o Call): outgoing arrow from the bottom of
the box. This arrow represents that the activity relies
on an activity already defined somewhere else in the
model or in another model.</p>
      <p>In an IDEF0 model, each arrow should also be
associated to a label which indicates the nature of the
dependency. Moreover, arrow lines are enforced either
to maintain a straight horizontal line or to break into
horizontal segments that are connected by perpendicular
lines.</p>
    </sec>
    <sec id="sec-3">
      <title>C. BPMN</title>
      <p>
        The BPMN notation has been defined to introduce a
modeling language that could be easily understood by
business users (e.g. managers, process owners, business
analysts, etc.), as well as by technical users (e.g. IT
analysts, IT developers, etc.) [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. The notation builds
on concepts defined by popular modeling languages,
such as UML, IDEF, and the classical workflow
language. BPMN provides three types of diagrams,
however only the Business Process Diagram (BPD) has
been used in this work.
      </p>
      <p>A BPD is a directed graph composed of flow objects
and connecting objects. A flow object is the main
describing elements within BPMN, and can be an event
(something that happens), an activity (process step) or a
gateway (the divergence and convergence of execution
flows). A connecting object is a line that connects
BPMN flow objects to specify the flow of activities in a
process.</p>
      <p>To organize activities in a process model, BPMN
provides the swimlane primitive, which is used to
represent roles, responsibilities and/or organizational
structures by means of pools (organizations) and lanes
(structures within an organization).</p>
      <p>Finally, the BPMN notation also provides means to
represent information. Artifacts represent information
relevant to the model but not to individual elements
within the process. Actually, they are used to augment
and describe a BPMN process. There are three artifact
types: annotations (to represent additional flow parts of
the model), groups (to organize tasks or processes), and
data objects (to specify input, output or stored data).</p>
      <p>Fig. 3 summarizes the main elements of a BPD
specified by use of BPMN.</p>
      <p>
        Model-based systems engineering (MBSE)
approaches have been widely applied to various systems
engineering domains and activities as these approaches
have shown increasingly benefits with respect to the
conventional document-based approaches [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. For
example:
•
•
•
      </p>
      <p>Communication improvement through a visual,
shared, and unambiguous representation of the
final system for the entire engineering team;
Risk reduction in the development process through
the progressive and continuous validation of
requirements and of the verification of proposed
solution (for example via integrated simulation or
formal verification)
Quality improvement through a rigorous and
computer-managed traceability of the specification
integrity and consistency over the entire
development process
• Productivity improvement, through a prompt
availability of traceability and impact analysis
scope, including also the increased reuse of
software and system components from the model
specification level already, and the automatic
generation of code for software systems.</p>
      <p>
        Leveraging on the above benefits, model-based
systems engineering approaches have been applied to
business processes engineering, which can be radical
(Business Process Reengineering, BPR) or incremental
(Business Process Improvement, BPI). Various works
can be found in literature about case studies, industrial
applications, technologies, and methodologies related to
model-based approaches. More rarely, these approaches
have been applied to support project management,
which has historically focused on the collection of
lessons learned and in the definition of tools for, e.g.,
planning, estimation and risk management. This paper
bridges the areas of model-based systems engineering
and project management with the application of a
model-based approach to the specification of a project
management method consisting of roles, principles,
project artefacts, and processes. Although the
application of MBSE is not new to support project
management (see, e.g., the model-based approach to
support the integration of aircraft systems described in
[
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]), to the best of our knowledge no contributions can
be found dealing with the application of MBSE to the
formulation of project management methods,
particularly related to PRINCE2.
      </p>
      <p>IV.</p>
      <sec id="sec-3-1">
        <title>MODEL-BASED REPRESENTATION OF PRINCE2</title>
        <p>The model-based representation has been developed
top-down in three steps:
1. Development of a process architecture in IDEF0,
to identify the high-level processes and their
interrelationships.
2. For each top-level process, one or more BPMN
diagrams were developed to show the activities,
the internal documents produced, and the
communication and synchronization with other
processes.
3. Development of tables and matrices for an
immediate indexing of all the diagrams, to further
ease the use of the model-based specification of
PRINCE2.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>A. Process Architecture in IDEF0</title>
      <p>IDEF0 was selected for the representation of the
process architecture as this language allows the organic
and systematic representation of models with an
increasingly level of details. Moreover, this language
inherently highlights the functional dependencies rather
than the temporal dependencies, which can conversely
be better represented in BPMN. Within this work, the
objectives of the process architecture are to:
• provide the users with a synthetic and conformant
representation of PRINCE2
• highlight the various high-level activities
performed in a PRINCE2 project
• formalize the process interdependencies to provide
an overarching framework that could provide a
“starting point” for the detailed modeling and an
“end point” for overall consistency verification.
• define the responsibility areas uniquely
• understand how resources are used
• identify key controls</p>
      <p>For completeness, we first represented the PRINCE2
function as the IDEF0 A-0 diagram, which is shown in
Fig. 4.</p>
      <p>Next, the process architecture has been developed in
three steps and two levels of details (phases and
processes). The first step deals with the functional
breakdown of all the PRINCE2 phases and processes
(see Fig. 5), the second with the representation of phases
and the third step with the representation of processes.</p>
      <p>Fig. 5 illustrates the diagram representing the
following PRINCE2 project phases: Pre-project (A1),</p>
    </sec>
    <sec id="sec-5">
      <title>Initiation stage (A2), Subsequent delivery stage(s) (A3) e Final Delivery stage (A4).</title>
      <p>Fig.6 instead represents the four PRINCE2 phases and
their interrelations according to a temporal
decomposition (i.e. each block groups the lower level
processes by a temporal proximity rather than a
functional similarity).</p>
      <p>Although this approach is theoretically debatable, it
offers the most intuitive representation for project
managers, who are primarily concerned with a
temporally sequential access to the model.</p>
      <p>The IDEF0 diagram also highlights the required
resources in each phase and the expected conditions
needed for their successful implementation.
Consequently, with only one figure, the project manager
can quickly acquire a more comprehensive view on the
respective part of the PRINCE2 specification.</p>
      <p>Fig. 7. IDEF0 Second Level – Expansion of A2 Process (Initiation Stage)
Each A0 activity block is then detailed into a more
refined IDEF0 diagram. For the sake of conciseness,
only activity A2 (Fig.7) and A3 (Fig.8) are detailed in
this paper. These diagrams represent the
interrelationships among the PRINCE2 processes
activated in the initiation and subsequent delivery
stages. As both stages involve the invocation of the
process “Directing a Project”, the respective block
activity is included in both diagrams. Inherently, this
double presence also explains the complexity in
managing the lower level BPMN diagram: the same
PRINCE2 process is activated in various points by
different events. The supporting tables will ensure that
the project manager is provided with full guidance for
the identification of the lower level diagrams. With a
basic understanding of the IDEF0 formalism, all the
above diagrams can be immediately read also by a
novice IDEF0 user, and therefore their accurate
narration is left to the interest reader.</p>
    </sec>
    <sec id="sec-6">
      <title>B. Detailed Process Definition</title>
      <p>
        The seven PRINCE2 processes are represented by a
set of BPDs in BPMN. The BPD allows for a higher
accuracy in the semantics of the activities to be
performed, as well as of the interdependencies.
Moreover, BPMN also provides symbols to represents
events and data, both essential for the definition of
process interdependencies. BPD diagrams have been
specified according to the modeling guidelines
introduced in [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ], while aiming to maintain diagrams
relatively simple and readable within an A4 page format.
The process mapping has progressed hierarchically
through the analysis of the PRINCE2 specification and
by applying the mapping guidelines described in [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ].
      </p>
      <p>
        BPMN intrinsically ensures the traceability by use of
hyperlinks provided by modeling tools (ADONIS in this
paper case [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]). However, with regard to the IDEF0
model, the traceability has been achieved by including
textual notes indicating the respective IDEF0 activity
block(s) and diagram into the top-level BPDs.
Concerning the model consistency, the internal
consistency is similarly ensured by the modeling tool
using the model syntax validation rules. Differently, for
the consistency between the BPMN diagrams and the
IDEF0 diagrams, it is manually ensured by using the
following mapping [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]:
      </p>
      <p>Eventually, the whole BPMN model resulted into a
hundred diagrams. Fig. 9 and Fig. 10 show the BPDs of
the processes “Initiating a Project” (A21) and “Directing
a Project” (A12, A22, A34, A44), respectively. These
processes are synchronized through the event “Request
to Run a Project”, which is triggered by the former
process and catched by the latter one. This key
integration aspect can be immediately inferred in both
diagrams by noticing the respective relationships
between the process pools and the triggering/catching
event symbols.</p>
    </sec>
    <sec id="sec-7">
      <title>C. Supporting Tables and Matrices</title>
      <p>The above IDEF0 and BPMN diagrams completely
represent the whole PRINCE2 specification. As these
diagrams are in a machine readable format, they can be
opened with the relevant modeling tools and be directly
navigated through the hyperlinks inherently associated
to the model elements. Currently, most of the project
management tools focus on the definition of project
plans or on the KPI-based monitoring/tracking of project
performance. Differently, the project execution requires
a pervasive human intervention in the implementation of
the tasks, and therefore it has received less attention for
automation opportunities. Consequently, when using the
paper-based version of the model, a project manager can
further benefit from indexing means to identify which
diagram(s) are to be retrieved. The indexing is
particularly needed for two reasons. The first reason is
that the IDEF diagrams provide a functional breakdown
that is to be linked to the lower level time-oriented
BPMN diagrams. The second reason is that the BPMN
diagrams are numerous and are not accessed
sequentially. For example, the project manager may
want to know which project actors are to be involved in
a process, or which processes should be started as a
consequence of an event occurring, or which process(es)
produces or consumes an internal product of the project
activity. In particular, the following types of tables and
matrices are made available along with the PRINCE2’s
IDEF0 and BPMN diagrams:
• an Overview Table, which describes the key features
of the process, including the purpose, the triggering
event, the involved actors, the list of the activities, the
triggered processes, and the produced/consumed
internal project output. The project manager may refer
to this table for consultation when preparing a process
execution.
• an Event Traceability Matrix, which identifies the
processes that can trigger an event and the processes
that should be activated when that event. The project
manager can consult this matrix to identify which
process should be executed when an event occurs.
• a Product-Process/Activity Traceability Matrix, which
identifies the process(es) that creates, confirms,
updates, or reviews an internal project product. This
matrix also provides references to the actors
performing the activity, offering therefore a
comprehensive view on all the actions performed on
the internal products. For example, the business case
is created in the process “Starting a Project”, updated
in the processes “Begin the Project” and “Manage
Stage Boundary”, and finally it is confirmed in the
process “Directing a Project”.
• an Activity Summary Table, which shows the list of
input and output items for each activity.</p>
      <p>Fig. 9. BPD of the process “Initiating a Project”
Fig. 10. BPD of the process “Directing a Project”</p>
      <sec id="sec-7-1">
        <title>CONCLUSIONS AND FURTHER DEVELOPMENTS</title>
        <p>PRINCE2 is a widely used standard and structured
project management methodology that can be applied to
various systems engineering application domains.
However, the PRINCE2 specifications can be complex
to learn and to apply as it defines a large number of
interleaved processes and activities that must be
orchestrated to implement the project execution. With
the objective of easing the learning and the application
of the PRINCE2 methodology, we have introduced a
model-based specification for the PRINCE2
specification. The specification consists in a process
architecture, a set of detailed process diagrams, and a set
of indexing tables to directly access the diagrams.</p>
        <p>The process architecture has been represented with
IDEF0 as the architecture is inherently structured
hierarchically in phases, processes, and their
interdependencies (inputs/outputs, resources, and
enabling conditions). The architecture consists of eight
diagrams: one diagram to represent the hierarchical
functional breakdown and seven diagrams to represent
the PRINCE2 specification from the context to the
individual PRINCE2 processes. Each of these processes
is mapped onto a detailed BPMN diagram, which is
further decomposed to reach the same granularity/detail
level to PRINCE2 specification. Overall, about one
hundred BPMN diagrams have been developed to cover
all the details of the PRINCE2 specification. These
diagrams can be immediately and directly accessed by
use of a modeling tool, and therefore they offer to the
project manager a web-like browsing tool for the entire
PRINCE2 specification.</p>
        <p>However, only the project management activities
related to monitoring &amp; control or to project planning
are currently supported by automated tools. Project
execution activities are specifically carried out without
any tool support, as these activities often require sound
judgement and specialist knowledge that are difficult to
automate by use of a software tool. Consequently, we
have also introduced a set of tables and matrices
(overview table, event traceability matrix,
productprocess matrix, activity summary table) to ease the
manual access of the diagrams. These tables and
matrices provide synthesized information on the
diagrams and a reference to the relevant diagrams. As an
example, an overview table summarizes the key features
of each process and activity, providing also a reference
to the respective diagrams. Similarly, the event
traceability matrix provides the project manager with the
information on which events can be triggered by which
process and which process is triggered by the events.</p>
        <p>Asides from the above motivations and advantages,
the model-based approach can contribute to provide a
wide number of additional benefits, such as
communication improvement, quality improvement,
risk reduction, etc., which are commonly experienced
when applying model-based systems engineering to the
analysis and design of complex socio-technical systems.</p>
        <p>
          Moreover, once the PRINCE2 specification is in a
machine-readable format, further exploitations can be
easily obtained also with current tools and technologies.
In line with the current capabilities of model-based
systems and simulation engineering [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ][
          <xref ref-type="bibr" rid="ref14">14</xref>
          ], we envision
three further areas of future exploitation for our model:
•
•
•
simulation of project management processes, for:
1. the analysis and design of innovative project
management methodologies
2. the optimization of organizational resources
3. the post-mortem analysis on completed (or
cancelled) projects
specification verification, to ensure the consistency
across all the processes and internal documents
graphical customization of the PRINCE2
specification for specific projects and
organizational contexts.
        </p>
      </sec>
    </sec>
  </body>
  <back>
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