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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>Banff Knowl
Acquis Knowledge-Based Syst Work</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="doi">10.1145/584369.584397</article-id>
      <title-group>
        <article-title>Reusing Components across Multiple Configurators</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Amartya Ghosh</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Anna Myrodia</string-name>
          <email>annamyr@dtu.dk</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Niels Henrik Mortensen</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Lars Hvam</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Management Engineering, Technical University of</institution>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Department of Mechanical Engineering, Technical University of</institution>
        </aff>
      </contrib-group>
      <pub-date>
        <year>1996</year>
      </pub-date>
      <volume>461</volume>
      <fpage>82</fpage>
      <lpage>91</lpage>
      <abstract>
        <p>1. The purpose of this paper is to examine the way in which an engineering company reuses components of existing configurators across multiple configurators. As the use of configurators has been extended across all lifecycle phases of products, product families, and services, companies tend to develop multiple configurators to support their business processes. Often, companies develop new configurators from scratch even though some existing configurators comprise components that serve a similar purpose. While the concept of reusability is discussed extensively in software and expert systems development literature, it has not been addressed in the existing literature on product configurators. In this study, the research team primarily focuses on the approach of reusing and sharing components from existing configurators to develop new configurators in a multi-configurator portfolio. We also examine the benefits and challenges of this reusability approach. The research is supplemented with empirical evidence based on an exploratory case study. The results demonstrate the way in which an engineering company uses and structures multiple configurators, the experiences with the concepts of reusing and sharing of configurator components and the lessons learned.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>INTRODUCTION</title>
      <p>The increased demand for highly customized product and service
offerings has led to companies adopting mass customization
strategies to reduce delivery times, lower costs, and to combat the
challenges of product variant proliferation. This increase in product
variation is accompanied by an increased amount of product
information. This information is traded among the customers, the
sales and the production departments at the company, and the
suppliers to generate valid customized product variants and the
requisite product documentation [1]. Companies use information
technology (IT) tools such as product and service configurators to
automate the handling of the product information [1].</p>
      <p>Configurators are knowledge-based IT systems, which fulfill a
configuration task. A configuration task is a special type of design
activity [2] facilitated by a number of components, their
corresponding properties and ports, and constraints which restrict
the number of feasible combinations associated with the
components [3]. Similarly, for service configurators, the
configuration models for configurable services comprise types,
their constituent attributes, and constraints organized in
generalization and aggregation hierarchies [4].</p>
      <p>
        The use of product configurators is associated with several
benefits, that have both direct and indirect impact on the lead time,
quality, and cost of the customizable products [1,5,6]. The
literature reports these benefits in relation to the different lifecycle
phases of complex configurable products [7], the impact on human
resources and sales performance [8], the return on investment of a
product configurator project [9] and the level of maturity of the
company [
        <xref ref-type="bibr" rid="ref11 ref13 ref2 ref20 ref22 ref32">10</xref>
        ]. Examples from case studies demonstrate the
quantitative value of these benefits [11,12].
      </p>
      <p>On the other hand, several studies report a number of challenges
that companies face in realizing the benefits from their projects.
These challenges are categorized in relation to IT systems, product
modeling, organizational issues, resource constraints, type of
products, and knowledge acquisition [13]. Versioning control [14],
ensuring data quality [15,16] and data maintenance [15] are some
additional challenges that companies face while implementing a
product configurator. A number of the previously mentioned
challenges arise because of the high number of product variants,
the complexity associated with the level of difficulty to model and
maintain configurable products within a configurator, and the
number of resources needed [17]. In the case of software and
expert systems, the use of the concepts of modularisation and
reusability has led to a reduction in development effort and risk and
maintenance effort [18]. A number of studies on product
configurators have addressed the issue of modeling a product
family within a configurator, by incorporating the principles of
product modularisation and product platform strategies into the
underlying product model and developing system-level structures
[19,20]. However, these studies do not address the implementation
of the concept of reusability across multiple configurators or the
benefits and challenges associated with the implementation of such
an approach in an industrial setting.</p>
      <p>Therefore, this study aims to address this gap in the existing
literature by exploring the experiences of companies reusing or
sharing components across multiple configurators. The practical
implications of this study are examined via a case study of an
engineering company using multiple configurators. The research
investigates how the configuration team at the company reuses and
shares components across multiple configurator projects and the
benefits and challenges associated with the use of the concepts of
reusability and sharing in the development of multiple
configurators.</p>
      <p>The structure of the article is as follows. Section 2 presents a
literature review that provides a theoretical background on the
reuse of parts or modules across multiple product architectures,
general software systems, expert systems, and configurators.
Section 3 presents the research method. Section 4 introduces the
case company and the landscape of its configurator portfolio, and
in section 5, the results from the case study are presented. Section 6
discusses the results from the case study in relation to the research
question and the existing literature base. Section 7 presents the
conclusions to the study and the areas of future research.
2</p>
    </sec>
    <sec id="sec-2">
      <title>THEORETICAL BACKGROUND</title>
      <p>This section provides an overview of the existing literature on
related topics such as the reuse and sharing of modules in software,
product platform design and expert systems and identifies the gap
in terms of reusability in configurators.
2.1</p>
    </sec>
    <sec id="sec-3">
      <title>Modularity and reusability in products and product families</title>
      <p>The concept of modularity has been discussed in depth in the
recent literature in relation to the concepts of mass customization,
product design, and complexity management [21]. The reason for
the development and the extended advancement of the modularity
concept, in both academia and industry, is related to the various
benefits that its implementation is bringing along.</p>
      <p>A module is defined as an “essential and self-contained
functional unit relative to the product of which it is part” [22]. The
standardized interfaces and interactions of each module enable the
creation of product variants by developing and producing a
combination of different modules. By pursuing a modularization
strategy, companies can achieve economies of scale while offering
greater product variety to their customers, increase strategic
flexibility by reusing modules across various product models and
model generations and concurrently develop the modules and
product components [23]. In order to successfully implement a
modularization strategy, the companies need to choose the suitable
degree of modularity in their products, effectively prioritize the
requirements of the company functions while designing the
modules and coordinate the modular product development process
across all the concerned organizational units [23].</p>
      <p>The modularity of a product is an important characteristic of its
architecture [24]. Based on the sharing of product architectures and
standardized interfaces [25], the product platform approach enables
companies to handle the proliferation of product variety. This
approach entails the sharing of components, processes, knowledge,
people, and relationships across a set of products [26].</p>
      <p>The use of a platform strategy leads to a reduction in the
development cost and time for new product variants. Moreover, the
consequent reduction in the volume of parts and the number of
associated processes leads to a reduction in material costs, logistics
costs, procurement costs, inventory costs, and sales and services
costs. [26]</p>
      <p>However, companies face several challenges while adopting a
product platform approach. Product planning and marketing
managers have to decide on the product variants that will meet the
demands of various market segments while saving development
and production costs. Designers face challenges in deciding what
product architectures to use in deriving product variants from
product platforms. As more departments with differing goals and
objectives get involved in the decision-making process, companies
also face difficulties in maintaining a balance between the
commonality and the distinctiveness of their products. [26]
2.2</p>
    </sec>
    <sec id="sec-4">
      <title>Modularity and reusability in software</title>
      <p>The reusability of software has been examined by academia in
depth during the last few decades [27,28], regarding approaches
and methods. With regards to engineering, there are three main
concepts of reusability of software identified: application system,
component and object and function reuse [29]. The entire
application system can be integrated into other systems, without
significant adaptations and changes to the reused system. An
example of this reusability concept could be a commercial ERP
system that is used by different companies with entirely different
product portfolios. The component reusability refers to cases of
reusing only a component of the whole system or sub-system to
another. For instance, libraries in software can be reused by several
systems containing information about different products. The last
concept describes the reusability of software components that
implement a single and well-defined object or function in a system.
An example of this is the reusability of the price calculation logic
described in a software component across several systems, such as
quotation solutions, ERP systems, and order placing systems</p>
      <p>As expected, there are several benefits associated with the
reusability of software [18]. One of the main benefits is the ensured
dependability of the software since the software has been already
tested in another environment. Moreover, the reuse of exiting
software leads to a reduction in development effort and the risk of
implementation. For commercial software, the familiarity of the
user with the system increases efficiency, productivity, and reduces
the risk of errors. In particular, when reusing components or
objects/functions of a system, it supports faster software
development in terms of time, costs and resources, and it allows for
specialists, who carry experience, knowledge and best practices
regarding the reused modules, to be involved.</p>
      <p>On the other hand, there are a number of challenges associated
with the concept of software reusability in any of the three forms
described before. The integration of a new piece of software into
the existing IT landscape or the integration of an add-on modular
component into an existing system usually requires customizations.
These customizations can lead to compatibility issues.
Furthermore, companies incur a high cost of hiring experts to make
these customizations to the existing software.</p>
      <p>Companies may also utilize a software-product line engineering
(SPLE) approach to develop software systems by reusing assets
created throughout the software product development lifecycle.
This approach is characterized by two lifecycle processes: domain
engineering and application engineering [30]. Domain engineering
deals with the development of the reusable assets, which constitute
the product line infrastructure [30]. Application engineering
involves combining these reusable assets with product-specific
assets to create the final software product [30]. Companies may
combine several inter-dependent SPLs to create a multi-product
line (MPL) to develop large or ultra-large software systems [31].</p>
      <p>The benefits associated with the implementation of the SPLE
approach include increased developer productivity, improved
quality, reduced maintenance efforts, reduced code size, reduced
consumption of resources, and reduced time-to-market of the
products [32]. However, companies utilizing the MPL approach
also face challenges in structuring the MPL models during the
domain engineering process [33] and handling the technical and
organizational dependencies between the constituent product lines
during the derivation of a software product by multiple users [34].
2.3</p>
    </sec>
    <sec id="sec-5">
      <title>Reusability in expert systems and product configurators</title>
      <p>As with software systems, several studies have explored the use of
the concept of reusability in developing expert systems [35]. An
expert system refers to “a computer program that represents and
reasons with knowledge of some specialist subject with a view to
solving problems or giving advice” [36]. It comprises a knowledge
base, an inference engine, a knowledge acquisition system, and a
user interface system [35]. At the highest level of abstraction, an
expert system can be decomposed into two components: the
knowledge base and the problem-solving methods, both of which
can be reused to build other expert systems [35].</p>
      <p>The creation of the knowledge base is a very resource-intensive
task and is often a bottleneck in the development process of an
expert system. Therefore, developers can achieve significant
savings in time and costs by reusing the knowledge base across
different problem-solving methods, even though the knowledge
base may require adaptation to suit the problem scenarios.
Developers can also reduce maintenance efforts by reusing
previously tested problem-solving methods across multiple
knowledge domains [35]. In certain studies, researchers have also
addressed the decomposition of the problem-solving methods into
constituent lower-level components in different environments,
using architectures such as INDEX [37] and PROTÉGÉ [38].
Moreover, certain architectures and specifications such as CORBA
[39] allow for the reuse of expert system components across
different platforms and different development environments.</p>
      <p>As configurators can generate valid configurations based on the
underlying configuration model, they are considered to be typical
examples of expert systems [40]. A couple of studies have
proposed approaches for making system-level configurations.</p>
      <p>An example of this approach is the SAP2 configurator that
integrates sales, product and production configuration using
specific sub-modules [19]. The configurator uses an underlying
configuration model for a product family that unifies the functional
view, the product component view and the corresponding
production operations and resources view, called the GBoFMO
(Generic Bill of Functions, Materials and Operations).</p>
      <p>Another approach for system-level configuration identified in
the literature is a configurator prototype that manages system-level
platforms and incomplete product configurations for
engineer-toorder (ETO) companies and project-based businesses [20]. These
projects consist of system-level configurations and multiple
product configurations. Each product configuration is decomposed
further into its constituent subsystems and parts. The system-level
configurations are based on high-level templates, containing the
system level parameters. The system configuration provides inputs
into the product configurations, while the product configurations
feedback any changes to the parameters to the system-level
configuration. The system-level configuration instantiates the
product configurations through the use of a common template and
domain-specific vocabulary.
2.4</p>
    </sec>
    <sec id="sec-6">
      <title>Benefits and challenges of reusability</title>
      <p>In the previously mentioned studies on the challenges of
configurator implementation and usage, a number of companies
were unable to realize the benefits from the implementation of
configurators. The reasons for this inability include difficulties in
acquiring, formalizing and managing product knowledge, handling
rapid product changes and the inability of the configurators to
cover the entire product portfolio [41]. Companies producing
highly complex products also faced challenges in clearly defining
the product families that would be represented in the configurators
[13]. Moreover, a number of companies faced challenges due to a
lack of resources for developing and maintaining the configurators
and developing integrations to other IT systems [42]. The
companies can reduce the development and maintenance efforts for
their portfolio of configurators by adopting the concepts of
reusability and sharing, as utilized in the design of product
platforms, general software systems, and expert systems, in the
development of new configurators. However, the aforementioned
studies on the SAP2 configurator and the system-level configurator
do not explicitly address how companies can adopt the concepts of
reusability and sharing in structuring multiple configurators and the
benefits and challenges they face in the implementation of such an
approach.</p>
      <p>Thus, there is a lack of empirical evidence into how companies,
which have successfully implemented multiple configurators,
structure their configurators, and what components are reused or
shared across different configurators. This study aims to address
this gap by conducting a case study at a company using multiple
configurators to find out how companies utilize the concept of
reusability in structuring their configurators and what benefits and
challenges they face by adopting this particular approach. To
achieve this goal, the following research question is formulated:</p>
      <p>RQ: How do engineering companies utilize the concept of
reusability and sharing to structure their product configurators?
3</p>
    </sec>
    <sec id="sec-7">
      <title>RESEARCH METHOD</title>
      <p>To answer the RQ, the research team conducted an exploratory
case study at a Danish engineering company utilizing the concept
of reusability and sharing of components across multiple
configurators to support the sales processes. The specific company
was selected as it is considered to be representative in terms of
using multiple product and service configurators to support the
sales processes pertaining to their ETO products. The company is
sufficiently mature as it has been using configurators for sixteen
years. The reason for applying case study research is to test still
unknown variables and not entirely understood phenomena in their
natural settings [43]. The unit of analysis in this study is the
configurator portfolio which has been built up by the company.</p>
      <p>Data collection was conducted in the form of semi-structured
interviews with members of the configuration team at the
company. The interviewees were selected based on their years of
experience, knowledge, and level of involvement in designing the
configurator set up. The research team interviewed the IT project
manager and the business owner from the configuration team as
both these team members had extensive experience in the
development, implementation and maintenance of the
configurators. The business owner is responsible for coordinating
with the stakeholders from the different business areas and in the
prioritization of new configurator projects. She has been working
on configurators at the company for the last seven years. The IT
project manager was responsible for the project management tasks
related to the configurators and supported the team in handling
some maintenance tasks on the configurators. She has been
working with the configuration team for nearly four years.</p>
      <p>The research team opted to conduct semi-structured interviews
to impose an overall structure to the ensuing discussion and to
provide a direction to guide the interviewees while allowing for
some flexibility for the interviewees. Based on the reviewed
literature on the concepts of modularity and reusability in physical
products, software systems and expert systems discussed in the
theoretical background section, the research team prepared a list of
questions, which are presented in the Appendix. The duration of
each interview was one hour.</p>
      <p>The questions address the topic of reusing and sharing
configurator components across multiple configurators and the
benefits and challenges that the company has faced while
implementing such an approach. The questions, categorized as
“Company-specific questions”, aim at providing an overview of the
case company’s experience in developing and implementing
configurators. The interviewee specific questions address how the
configuration team has set up multiple configurators and how they
have utilized the concept of reusing and sharing configurator
components across multiple configurators.</p>
      <p>As the research team was also investigating the aforementioned
approach from a business perspective, the last two
intervieweespecific questions address the impact of implementing this
approach. In particular, the interviewees were asked about the
benefits and the challenges of implementing a modular concept on
the product configurator portfolio. First, they were asked to answer
this question based on their experience and then they were
presented with a list from the benefits and challenges identified in
the literature, to ensure that all the relevant topics were taken into
account.</p>
      <p>The collected data used for the analysis were qualitative in
nature, primarily based on the interviews. Supplementary material
provided included schematics of the IT landscape and a
demonstration of the configurators, to allow the research team to
develop a better understanding of the configurator portfolio.
4</p>
    </sec>
    <sec id="sec-8">
      <title>CASE DESCRIPTION</title>
      <p>The selected case company is an engineering company, providing
solutions from specific equipment to complete plant solutions. The
company operates globally, serving the food, dairy, chemical, and
pharmaceutical industries, and has a yearly turnover of
approximately 305 million €. The complete solutions provided
include some standardized customize-to-order (CTO) products, but
they also require customized ETO products for specific customers.
As mentioned earlier, the company has been using configurators
for sixteen years, with the current portfolio of configurators
covering approximately 50% of the entire product portfolio of the
company. In the case of ETO products, the concerned configurators
are capable of generating full or partial configurations.</p>
      <p>The configurators support the sales and service phases of the
products and solutions offered to the customers, particularly the
tendering and procurement processes. The configuration team
consists of 5 people in total: the business owner, an IT project
manager, one configuration engineer focusing on product and
service modeling activities, and two software developers. The
software developers focus primarily on developing add-ons and
plug-ins to enhance the functionality of the configurators. They are
also responsible for the development and maintenance of the
integrations with the other IT systems being used by the company.
The team is supported by a super-user from each business area,
who is responsible for collating change requests from the end-users
of the configurators and documenting these requests in a dedicated
documentation system. Moreover, the configuration team is also
supported in the development and maintenance of a number of
configurators in a specific business area by another configuration
team. Only the configuration teams are allowed to make updates
and perform maintenance tasks on the configurators.
4.1</p>
    </sec>
    <sec id="sec-9">
      <title>IT landscape: Configurators and integrations</title>
      <p>The overall set-up of the configurators at the company can be
described in four levels. Figure 1 illustrates the distinction between
the different levels. The plant configurator describes the complete
plant, including all the specific equipment and the services related
to them. The plant configurator also contains some constraints and
knowledge about the specific plant type covered by the
configurator. Each plant is first decomposed into several systems,
specific to each plant. Each system-level configurator contains
knowledge about the variants of each system. On the equipment
level, each configurator contains product knowledge and
constraints pertaining to specific equipment. The company also
uses a global service configurator, which is used across the
equipment configurators.</p>
      <p>When configuring a plant, the plant configurator calls the
specific system configurators, which, in turn, calls the requisite
equipment level configurators. The service configurator provides
service information for different plants and equipment.
All the configurators are developed using the same commercial
configuration system software.
At the plant level, the plant configurators have integrations to the
internal software system for making engineering calculations, the
pricing and the quotation databases, the product data management
system for the generation of piping and instrumentation drawings,
the document generator system and the calculation portal that is
used for manual cost calculations and importing the values to the
ERP system for project budgeting purposes. At the equipment
level, the configurators are only integrated to the document
generator system.</p>
      <p>Apart from the integrations to external systems, the commercial
configuration system software that the company uses enables each
configurator to call other configurators at a lower level. From a
practical point of view, to configure a complete solution (plant),
the configuration process starts from the plant level. At this level,
the user decides on the plant systems and based on this selection,
the required equipment are then individually configured. However,
in certain scenarios, the end-users can also use the equipment
configurators independently, without having to configure any
overarching plants or systems. For example, end-users in the
procurement department might require the prices for a specific
configuration of particular equipment and therefore would only
need to use an equipment configurator instead of creating a
plantlevel configuration and a plant system-level configuration first.</p>
      <p>A super-user from each business unit is responsible for the
collation of change requests or bugs from the end-users of the
particular configurators under the purview of the business unit. The
super-users document their requests in a dedicated documentation
system, which the configuration team can use while updating the
concerned configurator models. After making a change to the
particular configurator model, the configuration team follows a
standard procedure to document the changes. Then, the IT project
manager approves the changes before they are released for use by
the business units. The configuration team also uses a version
control system for the configurator models allowing them to revert
to an older version of the configurator model in case any issues
arise from the changes made.
5</p>
    </sec>
    <sec id="sec-10">
      <title>RESULTS</title>
      <p>The following section presents and discusses the results of the case
study. It focuses on the implementation of the concept of reuse and
sharing of configurator components at the case company and the
benefits and the challenges the company has experienced using this
approach.
5.1</p>
    </sec>
    <sec id="sec-11">
      <title>Reusability and sharing</title>
      <p>The configurators have a high degree of sharing and reusing parts
of the system, both within the same level and across different
levels, as illustrated in Fig. 1. When reusing components from
existing configurators to develop new configurators, the
configuration team uses the product model from an existing
configurator, either entirely or partially, and adapts it to suit the
purposes of the new configurator project. For instance, two
equipment in two separate business application environments
might have product models which are similar, but one equipment
may be more complex than the other. In this case, the configuration
engineer may reuse the existing product model of one equipment,
either partially (by making some changes) or fully while
developing the configurator for the other equipment.</p>
      <p>Additional areas of component reuse across different
configurators at the same level relate to the reuse of logic
components, e.g. ways of calculating values and generating
documents. The components of the configurator model that are
reused are usually the ones that do not require frequent changes to
the structure of the product model.</p>
      <p>At the plant system level, the concept of sharing becomes more
apparent. As mentioned earlier, each plant is decomposed into a
number of systems, which in turn, are composed of certain
equipment. These plant-systems are unique to each plant. However,
the same type of equipment may be used to meet the needs of
different plant-systems and plants. In such cases, the equipment
level configurators are shared across multiple plant system
configurators at the plant system level. For example, if a family of
blowers can be used in two different plants, then the company only
uses one configurator to store the product knowledge, and the two
different plant configurators call that equipment configurator when
required.</p>
      <p>As the plant level configuration is highly dependent on the
business application environment, the responsible business units
are primarily responsible for deciding what can be shared, for
example, based on the material used for the different equipment
and the prices. The business units are responsible for the overall
setup of the plants and the constituent plant-systems and
equipment. When a particular business unit requests the
development of a configurator for new equipment, the
configuration team starts building a configurator model based on
the input from that business unit. However, based on the tacit
knowledge of the configuration team and the documentation
available on the existing configurator models, the team may decide
to reuse an existing model in another application environment and
adapt it to meet the needs of the current context. Furthermore, the
business units may also coordinate with the procurement
department to find any existing configurators which may already
cover their user requirements.
5.2</p>
    </sec>
    <sec id="sec-12">
      <title>Benefits</title>
      <p>The primary benefit reported during the interviews was the
standardization achieved across the business units in the company.
Standardization is a benefit that is usually associated with
configurators. In this case, the standardization refers to both the
products and the processes. The standardization covers not only the
product models that were modeled into the configurators but also
the sales processes supported by them, the roles and
responsibilities of the stakeholders, and the maintenance and
change tasks associated with the configurators. Having these
standard procedures in place allow the configuration team and the
business units to improve their efficiency, to improve
communication and keep track of the change requests and changes
to the configurator models.</p>
      <p>Furthermore, the multi-configurator set-up allows for a more
modular representation of the product portfolio, including both
individual products but also complete solutions. In particular, the
introduction of the plant-system configurators supported the
decomposition of the plant into its constituent systems, which
resulted in rendering the development, maintenance, and testing
tasks much easier and quicker.</p>
      <p>The interviewees assigned more importance to the benefits of
standardization of the associated processes as compared to the
reduction in the development, maintenance, and testing efforts.
Nevertheless, there are variations identified regarding the time
spent of these tasks. In particular, the development time for an
equipment configurator is approximately six months along with an
additional one or two months allocated for initial testing, whereas
the plant configurators take around one year to develop. During the
development phase of a configurator project, the effort spent in
knowledge acquisition is more significant compared to the actual
effort dedicated to the modeling of the configurator.</p>
      <p>With reference to handling changes, the interviewees again
highlighted the improvements in efficiency. These improvements
arise due to the differences in frequencies of change requests
across different levels. For instance, the plant configurator models
were quite stable and required one or two changes annually. Since
the frequent changes are generally limited to the equipment
configurators, the maintenance and testing effort is lower as
compared to the effort required for maintaining and testing the
plant configurators. By having a clear overview of the tasks
required and to what level of the configurator portfolio they are
assigned to, the team can predict the maintenance efforts more
accurately and improve the efficiency of executing these tasks</p>
      <p>Another benefit highlighted is related to improved
communication and knowledge sharing in the company. The
particular setup of the configurator portfolio allows for better
communication among various stakeholders, especially
crossorganizational, e.g. when a business unit raises a request for new
configurators with the configuration team. In such a scenario, the
configuration team can use existing configurators for similar
equipment or plants within the same or different application
environment to show the scope and the functionalities, which the
configurators offer, to the stakeholders from the business unit. In
that sense, the reusability refers both to the configuration models
and the knowledge and experience for the processes supporting the
configurator.
5.3</p>
    </sec>
    <sec id="sec-13">
      <title>Challenges</title>
      <p>On the other hand, the interviews revealed several challenges
that the case company is facing while implementing the concepts
of sharing and reusability across the different configurators. The
main challenge concerned the coordination of the teams. As
mentioned earlier, two configuration teams are responsible for
developing, implementing and maintaining the configurators and
their integrations to other IT systems. If an equipment configurator
model is updated without informing the rest of the team, then this
might adversely affect the functioning of the overarching plant
models containing that equipment configurator. The interviewees
emphasized the coordination between the teams to ensure that such
issues would not arise while making changes or updates to existing
models. This is because the case company operates globally and
the geographical location differs among the team members. The
coordination related challenges are also in terms of roles and
responsibilities. Even though the set-up of the configurators ended
up supporting the transparency of the roles and tasks, in the
beginning, it was not clear how the distinction was made and how
the changes to the configurator models were communicated to the
stakeholders.</p>
      <p>Version control is another important challenge faced by the
company. While the configuration team utilizes a versioning
control system for the entire set of configurators, the team still
faces a challenge in deciding which version of the product model to
save. When the changes to any of the configurators are limited,
(e.g. update of prices), the configuration team does not save the
previous version first before making the changes. However, when
the change affects several levels of the configurator set up, the
team requires more time for implementation and testing. In this
case, the previous version is saved as it is significantly different
from the updated version. Another challenge faced by the
configuration team is the maintenance of compatibility across the
plant configurators, the plant-system configurators and equipment
configurators. In certain situations, the changes made to the plant
configurators result in errors if the lower-level models are not
updated accordingly.</p>
      <p>The company also faces challenges in deciding on the role of
the business units in the scoping and decision-making phases of the
configurator development projects. The business units are
responsible for making decisions regarding the overall structure of
the configurators. They also play a crucial role in defining the parts
of the configurators that are shared based on their alignment with
the strategic goals of the company and the market needs. The initial
user requirements, that are set from the business units, always need
to be adjusted, requiring several iterations and quite often the final
result is very different from the initial one.
6</p>
    </sec>
    <sec id="sec-14">
      <title>DISCUSSION</title>
      <p>This study addresses the issue of how engineering companies using
multiple configurators utilize the concept of reusability and sharing
of configurator components in developing their configurators, and
the benefits and challenges that the companies face in adopting this
approach. The study presents the case of a Danish engineering
company, which has been using configurators to configure ETO
plants and the constituent plant-systems and equipment.</p>
      <p>The findings from the literature study indicate that the concepts
of reusability and sharing have been extensively examined in the
fields of product development, software systems, and expert
systems. In the case of products, the use of reusable modules and
product platform strategies benefits companies by leading to a
reduction in development time, cost of new product variants,
manufacturing costs, and inventory costs. In case of software
systems and expert systems, the reuse of components, such as
libraries, problem-solving methods, and knowledge bases, lead to
the reduction in development, testing and maintenance effort
associated with these systems. These findings from the literature
study, along with the results from the case study, provide an
answer to the RQ. The empirical evidence demonstrates how an
ETO company develops multiple configurators to support its
business processes by reusing and sharing different configurators
and configurator components. It also explains how these concepts
are utilized when developing new configurators for different
business units of the company. Furthermore, the study also
addresses the benefits and challenges associated with the
implementation of such an approach.</p>
      <p>The way in which the case company structures their
configurators into different levels is similar to the system-level
configuration approach proposed in [20]. In both the approaches,
the system-level (plant-level, in case of the case company)
configurator is modeled first, followed by the modeling of the
constituent configurations. Both approaches also allow for partial
configurations for ETO products. However, the system-level
configurator prototype, as described in [20], does not address the
issue of using the concept of reusability and sharing of configurator
components across multiple configurators covering different
projects or ETO products and its benefits and challenges. The
benefits that the case company has generated from the use of the
concept of the reusability and sharing of configurator components
are similar to the benefits of the reuse of knowledge bases and
problem-solving methods in expert systems [1,5]. However, the
interviewees noted that the development time of the model itself
was insignificant compared to the time required for product
knowledge acquisition from the business units.</p>
      <p>With reference to the challenges of implementing a modular
approach to the set-up of the configurator portfolio, the findings
from the case study are aligned with the findings from the literature
[13,14]. Change management, knowledge acquisition and
maintenance of the models are the main issues addressed in the
findings of this research and can be primarily associated with the
concepts of sharing and reusing parts of the configurators.</p>
      <p>These findings provide strong empirical evidence to support
managerial decisions in terms of designing and structuring a
configurator portfolio. The insights from the case study can be used
as guidance when defining the scope of a multi-level configurator
set up and the establishment of the cross-organizational
collaboration among the teams involved in the development
process.
7</p>
    </sec>
    <sec id="sec-15">
      <title>CONCLUSION AND FUTURE</title>
    </sec>
    <sec id="sec-16">
      <title>RESEARCH</title>
      <p>The focus of this study is on examining the concepts of reusability
and sharing across multiple configurators. While these concepts are
well established in the fields of product modeling and software
development, they have not been addressed in depth in relation to
product configurators. The research team conducts a case study to
investigate how these concepts are implemented in an industrial
setting. The results from the literature review and the case study
provide an answer to the developed RQ on how the concept of
reusability in configurators is being used by engineering
companies.</p>
      <p>This study contributes to the existing knowledge on the
modeling and scoping of configurators by looking at how an
engineering company structures multiple configurators for
configuring ETO products using the concepts of reusability and
sharing of different configurator components. Practitioners in the
industry can also gain some insights into adopting these concepts
while modeling and scoping product configurator projects, as the
case company is representative of engineering companies
producing complex ETO products and utilizing multiple
configurators to support their business processes.</p>
      <p>This study focuses only on one case company and how they use
the concept of reusability and sharing of configurator components
to structure multiple configurators. Consequently, the discussion of
the benefits and the challenges, which arise out of the usage of this
concept, pertain only to the specific case company and the scope
and structure of their configurators. Therefore, future work will
focus on increasing the number of case companies, thereby making
the results of the study more generalizable to the industry at large.</p>
      <p>Another limitation of the study relates to the role of the
interviewees. For this study, we have interviewed only the business
manager and IT project manager on the company’s configuration
team. However, the business and technical units are responsible for
the underlying product architectures that are modeled in the
configurators. Therefore, in future work, we aim to interview
business unit stakeholders at the case companies to incorporate
their insights into the way in which the concept of reusability and
sharing is implemented and the benefits and challenges that they
perceive arising out of the implementation of this approach in
developing configurators.
1.
2.
3.
4.
5.</p>
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