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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Prioritizing Products for Profitable Investments on Product Configuration Systems</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Sara Shafiee</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Lars Hvam</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Poorang Piroozfar</string-name>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Mechanical Engineering Department, Technical University of</institution>
          <country country="DK">Denmark</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>1Product configuration systems are among the most popular expert systems for automating sales and manufacturing processes. Therefore, there are numerous studies on the qualitative benefits and quantitative profitability of configurators considering the required investments. This paper uses real case company data to demonstrate the most cost efficient and viable products for investment in configurators by calculating the profitability of the product types. ABC analysis (A, B and C categorization) is conducted to calculate the net profit and gross margins to be able to classify the products based on the available 3-years data. We categorize the products into A-, B- and C-products based on ABC analysis and Pareto principle to calculate both the net profits and sale quantity of different product types. The demonstrated case study reveals that the analysis of the products based on ABC analysis of the quantity of sales and net profits will be a suitable solution to prioritize and predict the most financially viable investments for the future configuration projects.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1 INTRODUCTION</title>
      <p>Configuration systems are the expert systems developed through
incorporating information about product features, product
structure, production processes, costs and prices [1]. Configuration
systems support decision-making processes in the engineering and
sales phases of a product, which can determine the most important
decisions regarding product features and cost [2], [3].
Configuration systems can bring substantial benefits to companies
such as, shorter lead time for generating quotations, fewer errors,
increased ability to meet customers’ requirements regarding
product functionality, use of fewer resources, optimized product
designs, less routine work and improved on-time delivery [1], [4]–
[6].</p>
      <p>Although advantages of configuration systems are evident, there
are still some difficulties associated with required high investment
[1], [7] and the chances of failure [8] in their implementation
phase. Hence, researchers attempt to provide the empirical data
from case companies to illustrate the potential expectations and
risks associated with configuration projects [3]. Besides, increasing
complexity is considered a major cause for rising costs and
deterioration of operational performance, leading, in particular, to
decreased quality, long delivery times, delayed deliveries, and low
process flexibility [9]. Therefore, companies need to control the
levels of complexity and how reductions in this regard can
positively affect their competitiveness in the market.</p>
      <p>
        To be able to gain the benefits of configurators, great effort and
investment must be accepted [3]. There are several research which
discuss about the high investments on configuration projects [8],
[
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. This research uses a case study to provide some guidelines on
how to prioritize and decide about the investment on configuration
projects. Although the literature provides a variety of methods to
support the decision about the investments on configuration
systems, there are enough guidelines to determine the most
profitable projects and receive the highest benefits from
configurators’ development. Hence, the companies need to decide
about the types of products to be prioritized for Configurators’
developments.
      </p>
      <p>The aim of this paper is to evaluate the investment on
configuration systems and predict their profitability using the data
from the product portfolio at the case company. More specifically,
the objective of the paper is to do the ABC analysis in order to
categorize different groups of the products based on the net profit
and sale quantity to be able to prioritize them. This prioritization
will guarantee the profitability of the configuration project and the
correct decision to invest on configuration systems’ development.
The paper will investigate the following question:</p>
      <p>RQ. How can industrial companies increase the benefits
through a profitable investment on the configuration systems by
prioritizing the products?</p>
      <p>In this paper, we chose a case study with highly engineered
products and evaluate one of the whole product family to
determine the most profitable products. Through the ABC analysis,
company can decide to invest on configuration systems for the
most profitable product types.</p>
      <p>Firstly, we carried out the ABC analysis on a specific product
portfolio from 2011 to March 2013. Secondly, we classified the
products as A-, B- or C- by calculating their sales quantity and net
profits. In this research, we query the real data from the selected
case company to compare different products and suggests the
company to invest on configuration systems based on this analysis.</p>
    </sec>
    <sec id="sec-2">
      <title>2 LITERATURE STUDY</title>
      <p>In this section, the relevant literatures for analyzing the complexity
of the products and process in enterprises are reviewed which will
then be utilized to support the choice of ABC analysis. Then, ABC
analysis is introduced. The ABC analysis will then be used to
determine the most suitable investment for the configuration
projects in the future.</p>
      <p>Copyright © 2019 for this paper by its authors. Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).</p>
    </sec>
    <sec id="sec-3">
      <title>2.1 Product and process complexity</title>
      <p>
        Product architecture is widely recognized as the main factor of
product complexity [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ], and product architecture management
enables the efficient design of new products that are targeted at
individual market requirements [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. Besides, product architecture
would help control the structure of the product and the number of
product variants, both of which affect the performance of sales,
engineering, the production/supply chain, distribution, and
aftersales service [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ].
      </p>
      <p>
        One of the main reasons for increasing product complexity is
the vast product variety to be offered to the customer [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ].
However, researchers offered various approaches and techniques to
both recognize and solve the complexity challenges in the product
range [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. Blecker et al. [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ] described how to apply mass
customization to eliminate the process complexity caused by the
increasing variation in the product architecture, inventory, and
order-taking process. On the one hand, applying a pure
customization strategy would results in increasing product variety
and the customer-order decoupling point moves towards the front
end [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ].
      </p>
    </sec>
    <sec id="sec-4">
      <title>2.2 ABC Analysis of the product range</title>
      <p>
        The analysis of the product range is another fundamental step
towards developing a configuration system [2]. It should help to
provide an overview of the company's product range and describe
the necessary product knowledge to be incorporated into the
configuration system. One approach is to start the modularization
and standardization project before starting a configuration project,
so that basically a ‘clean up’ is performed in the product program
and the associated IT systems [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ]. Another approach, for instance
in sales configuration system, is to consider which variants are to
be offered to the customers [2]. After this, it is ‘market
mechanisms’ that decide which variants of the products are needed.
      </p>
      <p>
        In order to clarify which variants should be offered to the
customers, a project team should clarify some important facts
about the company's product line, such as the product range
readiness to be dealt with in a configuration system, the most
profitable products, variants to be offered to the customers, etc. [7],
[
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. One way to create an overview of the product range, as well
as defining what should be entered into the configuration system, is
to set up an ABC-analysis. The purpose of applying this type of
analysis is to identify (and, later, possibly eliminate) product
variants that contribute only minimally to revenue but add
significantly to the complexity. The ABC-analysis is a
categorization method for dividing items into three categories; A,
B and C. A-items are the most valuable economically, while
Citems are the least valuable [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. This method aims at drawing
attention to the critical few A-items and away from the many trivial
C-items.
      </p>
      <p>
        The ABC-analysis is based on the Pareto principle, which states
that 80% of the overall revenue comes from only 20% of the items.
In other words, demand and profit is not evenly distributed
between items: top sellers vastly outperform the rest. The ABC
approach states that, when reviewing the product range, a company
should rate items from A to C, based on the following rules [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ]:
      </p>
      <p>A-items are goods, where the economic value is the highest.
The top 70-80% of the total annual revenue of the company
typically comes from only 10-20% of the items.</p>
      <p>B-items are the interclass items, with a medium dollar value.
Around 15-25% of the total annual revenue typically comes from
20-30% of the items.</p>
      <p>C-items are, on the other hand, items with the lowest dollar
value. Around 5% of the total annual revenue typically comes from
50-60% of total items.</p>
      <p>
        The ABC-analysis therefore gives the company the possibility
to focus their energy on a few critical items. However, a similar
analysis can be undertaken for the customers of the product range
to determine which ones are the most profitable. Therefore, for
each customer (or group of customers), the contribution margin
and the revenues are plotted in a diagram in the same way as
described for products [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ].
      </p>
    </sec>
    <sec id="sec-5">
      <title>3 RESEARCH METHODOLOGY</title>
      <p>The relevant literature was reviewed to clarify the present study’s
position in relation to existing research. In this respect, the
literature related to product and process complexity has been
studied. Moreover, the literature demonstrates the solution to
identifying the product/process complexities and ABC analysis
which will determine the most profitable product types. The
complexity identified by calculating the net profit and gross
margin.</p>
      <p>
        In this article, we use single case study to evaluate the
propositions in one ETO (Engineer To Order) company. The single
case study can be described as having a holistic, representative
design with a single unit of analysis (the case company) [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ]. The
case is representative because the company is typical of many
major manufacturers that have had problems managing product and
process complexity. As this type of case study methodology
pertains to a single case, it is possible to generate only an analytical
generalization, as opposed to a statistical one [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ]. We analyzed
the results from product portfolio during the 3 years at the case
company. Case-based research seeks to find logical connections
among observed events, relying on knowledge of how systems,
organizations, and individuals work [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ], [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ].
      </p>
      <p>The entire project was followed by three researchers. The
initiative of the research was the decision of the case company to
invest on configuration systems and their challenges regarding the
product prioritizations. Hence, the research idea was to explain the
product portfolio complexities and profitability. However, the main
goal was to illustrate the most profitable products and help improve
ROI (return on investment) for successful implementation of
configuration systems.</p>
    </sec>
    <sec id="sec-6">
      <title>4 THE CASE STUDY</title>
      <p>The company is an international business Engineer-To-Order
enterprise which provides specialized solutions within the field of
marine tank management for marine and offshore industries.
Within some of the areas of valve remote control, ballast and
service tank gauging, as well as cargo monitoring, the company
strives to open up new possibilities for more uptime, higher
productivity and safer, more reliable conditions for all types of
ships and offshore units. This project will focus exclusively on the
products ranges in the valve remote control systems at the case
company and their after sales department. The reasons for selecting
the case company are: (1) it has highly engineered and complex
products, (2) there is an urgent need for developing configuration
systems and elimination of time and resources for sales and after
sales processes; (3) the company has a huge range of product types
with different net profits and sales quantity; (4) it offers a unique
level of access to project data.</p>
      <p>The whole product range in the remote valve control department
has been investigated and all the relevant data related to the net
profits, gross margins and quantity of the sales has been extracted
and analyzed. If the case company uses configuration systems
instead of the ongoing situation, they could save up to 1.162.505
DKK per year by using a web-based configuration system.</p>
      <p>In order to invest on the configuration systems, the first step is
to categorize and determine the business cases by reviewing the
product ranges and determine the most profitable products (among
all product types) in valve remote control system to invest in. One
approach is to start a modularization and standardization project
before starting a configuration project, so that basically a ‘clean up’
is performed in the product program and the associated IT systems.
Another approach is, for example, in sales configuration system, to
consider which variants are to be offered to the customers more
often with higher profitability. After this, it is ‘market mechanisms’
that decide which variants of the products are needed or which
ones are the customers’ most popular and company’s most
profitable products.</p>
      <p>In order to clarify which variants should be offered to the
customers, a project team should clarify some important facts
about the company's product line, such as: is the product range
ready to be dealt with in a configuration system? Which products
are the most profitable? Which variants are to be offered to the
customers? etc. To make this clear, it is necessary to carry out a
process in the company, where all the different stakeholders (sales
staff, product developer, production staff, purchasers etc.) come
together to form a team, to create an overview of the overall
product range and determine which variants can be offered via
configuration system.</p>
    </sec>
    <sec id="sec-7">
      <title>5 RESULTS</title>
      <p>In order to find out which products are the most profitable within
the case company, an ABC classification was made based on how
many percentages of the total net profit the different products
return. The idea of an ABC analysis is to categorize the products
into three different categories; A-, B- and C- products. This is done
in order to estimate the importance of the products sold at the after
sales department. A-products are the most important, while
Cproducts are the least important.</p>
      <p>In accordance with the Pareto principle, this analysis has
categorized the products that return 80% of the total net profit as
A-products, while the products that return 15% are B-products and
the products that return the remaining 5% are C-products. Figure 1
demonstrates an ABC classification of the 4345 types of products
that were sold in the period from the beginning of 2011 to March
2013 at the case company.</p>
      <p>The ABC analysis shows that only 389 (9%) of the 4345
products are A-products, 744 (17%) products are B products, while
a staggering 3212 (74%) products are C-products. This
classification provides a general overview of the products, which
are the big sellers that should be kept under very tight control, but
also of the products that are not so profitable, and which may take
up too much inventory space thereby tying up too much capital
investment. The classification of products can be helpful in the
process of selecting those products, which should be entered into
the configuration system.</p>
      <p>Figure 2 illustrates the relationship between the net profit of the
categories and the amount of products in the categories. The figure
shows that 9% of the products return 80% of the total net profit,
while 74% of the products only return 5% of the total net profit.
Figure 2 also confirms the theory of the 80/20 rule in the Pareto
principle (see Section 2.2), and illustrates that a small part of the
case company’s products return the vast majority of the earnings.
Hence, the case company should be especially attentive to their
class A-products. In terms of selecting products for the
configuration system, we suggest that inserting the A-products into
the configuration system should have first priority.</p>
      <p>Figure 2 also shows that B-products (17%) return 15% of the
total net profit. If or when the configuration system should be
extended beyond inserting A-products. Finally, 74% of the
products return only 5% of the total net profit. However, this
means that the order-sales process takes up an excessive amount of
time and resources on handling the sales of small and unprofitable
products.</p>
      <p>Table 1 shows a selection of product types that were classified
as A-, B- or C-products. The products belonged A-, B- or
Ccategories are grouped in different types based on the highest to
lowest net profits. The reason for using “Type” is to avoid the
products names due to the confidentiality. This means, that for
instance the type 1 cell under “A-products” shows the total sales
numbers of all the variants of type 1 that were classified as
Aproducts; while the type 1 cell under “B-products” shows the total
sales numbers of all the variants of type 1 that were classified as
Bproducts. When selecting product types to appear in Table 1, the
Aand B-products were selected by the highest net profit, while the
Cproducts were selected based on the highest quantity. The reason
was that C-products doesn’t have significant net profit while the
company might sell them in high quantity.</p>
      <p>Table 1 illustrates, that it is advantageous to insert the Type 1
variants from Class A into the configuration system, since they
alone return almost 21% of the total net profit. If or when
Bproducts should be inserted into the configuration system, then it
would be advantageous to first insert the product variants that are
the most profitable. The table also shows, that in C-product, for
example type 1 and many other small products are sold in big
quantities, but are not contributing much in the total net profit. In
order to save time and resources on selling these unprofitable
products individually, case company should stick to selling them
only in package solutions (set of seals, common parts etc.). In a
configuration system rules could be made in order to make sure,
that these small products can only be sold in packages, which could
be helpful for the salespersons because configuration system would
automatically reduce time and resources in the order-sales process.
However, it is obvious that configuration system can save
significant amount of time for the products with high quantity in
case the case company desires to continue with the same scenario.
The aim of this study was to prioritize the products in one product
portfolio in order to have the most profitable investment on product
configuration systems. The empirical data is gathered from an ETO
company based on the analysis of 3 years’ worth of data. In detail,
the gross margin and net profits calculations verifies the Pareto
principles (which states that 80% of the overall revenue comes
from only 20% of the items). For this specific example, 80% of the
net profits is coming from 9% of the products. Then, more
calculation is done to determine the quantity of the sale. The
categorization of the products is carried out and tabulated for cross
examination.</p>
      <p>In addition to the ABC analysis, the inventory turnover was
investigated in order to see if there were any items lying still and
thereby tying up too much capital. Furthermore, it was investigated
whether or not the after sales department is creating orders, which
are not returning any profit for the company, for example if the
resources spent on handling the order exceed the profit of the
order. It was found that 2% (122) of the orders were not returning
any profit. This was not investigated further, since the number was
not considered critical. However, it should be mentioned that a
configuration system would have eliminated unprofitable orders
altogether.</p>
      <p>The analysis led to the conclusion that the investment on
configuration systems can be done based on the product
prioritization. The first reason is that they are the most profitable
products at the company and the benefits are remarkable. The
second reason will be due to the high quantity of sales which
means the amount of time and resources to produce and sell these
product types are significant. Hence, developing a configuration
system for these product types will save a considerable amount of
man-hours and a striking market benefit.</p>
      <p>This research in the first step is using the ABC analysis method
to prioritize the product types. Secondly, we did some additional
analysis to categorize the product for a profitable investment in
configuration projects. This study considers only one case
company and one case product and assumed as an exploratory
research. Therefore, it requires further research and additional
cases to use ABC or other methods to prioritize the products to
develop configuration systems. Also, the verification of the results
is appreciated which requires a longitudinal study after years of
configurators’ implementation at the company and in a
comparative case study.</p>
    </sec>
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