Perancangan konsep alat timbang untuk perkebunan kelapa sawit 12 Jurnal
DESIGN OF DIGITAL HANGING SCALES FOR OIL PALM PLANTATION
Pringgo W. Laksono 1,a, Roni Zakaria 1,b, Pandu S. Nugroho1,c
1
Department of Industrial Engineering, Faculty of Engineering, Sebelas Maret Unversity Surakarta,
Indonesia
a
b
pringgo@ft.uns.ac.id, 2012.ibnu@gmail.com, cpandusandito@gmail.com
Keywords: consumer requirements, concepts design, digital hanging scales, morphological chart, weighted
criteria, palm oil scale
Abstract. Indonesia produces about 44% of world’s palm oil. This is supported by the palm
plantation area owned by Indonesia reached 9.2 million hectares, or twice as large as Malaysian palm
oil. With large oil palm area, controlling process will be difficult to do and causing the chance of
weighing data manipulation which make a loss for stakeholders of oil palm plantations. To minimize
the chances of weighing data manipulation, this research aims to generate design of digital scale
according to the needs of stakeholders in the oil palm plantations. Based on consumer requirement,
this research has generated several concepts are combined with morphological chart. By using
weighted criteria, a design of digital scale has selected from several concepts. This study also
complements the selected concept by the architecture design, which aims to describe the physical and
functions of the components of the product and also the relationship between the components. The
final design makes the digital scale capable to send weighing data and location using GSM module,
which can minimize the possibility of weighing data manipulation.
Introduction
Indonesia produces about 44% to 47% of palm oil production worldwide [1, 2]. One of the factors
that make Indonesia able to dominate the world market of palm oil is the palm plantations owned by
Indonesia is very large, which is estimated at around 9.2 million hectares, or twice the area of land
owned by Malaysia [2 – 5]. In the other hand, the productivity of the Indonesian palm plantations is
still low because the land is owned by Indonesia reaches twice the land area of Malaysia but the
number of total production was only about 2 million tons of production [6, 7].
With a very large plantations, Indonesia should have accurate data about the productivity of the land
to determine the policies relating to the stability of the need for renewable energy supply. In fact,
there are still problems in the management of oil palm harvesting of data that is the weighing data
manipulation lands production of palm oil. PTPN V identifies a decrease in the production of palm
oil between 15-20 tons per day or lose a profit of 60 billion per year as a result of weighing data
manipulation [8]. The data manipulation performed by the interpreter weigh indicated by reducing
the weighing results of actual data. It reduces the income that land managers will lower interest land
managers in managing oil palm land that would adversely affect the efforts to maintain the
productivity of oil palm land.
Currently palm plantation in Indonesia is generally managed by a third party, are PTPN (State),
processing plants (Private), and civil society groups. Land management, especially in the weighing
process is still done manually with less supervision. With this kind of process weighing, weighing
data manipulation is still very possible to do so that the mechanism which can reduce the possibility
of manipulation of weighing data. This study intends to create a mechanism that can prevent the
manipulation of weighing data.
Methodology
This research was conducted with approaches as shown as by Fig. 1. First step of this research is
identify costumers requirements. Customer requirements obtained from interviews with the owners
of oil palm plantation. There are 10 owners of oil palm plantation who became respondents. Customer
requirement is converted into a technical solution for the preparation of the draft. Technical solution
obtained with the focus group discussion by experts. In addition, also conducted benchmarking with
competitors' products. Once arranged several concepts, it will be filtered and made an assessment of
the concept. After getting the results will be made product scheme
Start
Product
Planning
Problem
Identification
Collecting Data
Processing
Data
Analysis
·
·
Identify Customer Needs
Collecting customer needs
Interpretation Customer Needs
·
·
·
Preparation of concept
External and Internal search
Product Function Description
Morphological Chart
·
·
Concept Selection
Filtering concept
Assessment concept
·
·
Product Architecture
Product scheme
Grouping Elements Products
Analysis
Conclusions
Conclusions
Finish
Fig.1 Methodology
Result and Discussions
First step of this research is identify costumers requirements. Customer requirements obtained
from interviews with the owners of oil palm plantation. Customer requirement is converted into a
technical solution to generate several alternatives concept. By using weighted criteria, a design of
digital scale has selected from several concepts. After the concept has selected, this study continued
and finished by architecture design of digital hanging scale.
Identify Costumer Needs
Identify customer needs done by organizing focus group discussions with researchers and
interviewed consumers who use hanging scales. Customers who responded to the interview is the
consumers who use hanging scales for plantations. The result of costumer requirement is shown at
Table 1.
Table 1 Costumer Requirements
No.
1
2
3
4
5
6
7
8
9
10
Costumer Requirements
I want to look back on weighing has been done
Can be integrated with computer
I want the operator does not need to record the weighing results
I want the operator can not play the numbers hasi weighing
Hanging scales must be waterproof
Hanging scales do not have to frequently replace the battery
Hanging scales should be easy to use so the operator does not need to learn more
Scales used must be durable
It would be easier if you do not need to replace the battery
I need to know the weighing being performed
Concept Preparation
Conceptualization stage will be divided into four steps, namely are internal and external searches,
description of the function of the product, and morphological chart. Here are the stages of
Conceptualization.
Internal search
The Internal search conducted to extend the ideas to find a solution of the identification of
customer needs. Internal search conducted by a discussion with the parties within the team
environment.
Table 2 Internal Search
No
Costumer Requirement
Technical Solutions
1
2
3
4
5
6
7
8
9
10
I want to look back on weighing has been done
Can be integrated with computer
I want the operator does not need to record the weighing results
I want the operator can not play the numbers hasi weighing
Hanging scales must be waterproof
Hanging scales do not have to frequently replace the battery
Hanging scales should be easy to use
Scales used must be durable
It would be easier if you do not need to replace the battery
I need to know the weighing being performed
Weighing data can be stored and recalled
Using a USB or RS232 port
Weighing data directly sent to the management computer via gsm
Weighing data directly sent to the management computer via gsm
tool material made of waterproof material
Battery capacity is increased or using an internal battery
Simple interface (just turn on the switch and instantly ready for use)
strong casing material selection
Used internal battery
Added GPS module to define the location of the weighing
External search
External search as well as benchmarking with competitors' products or products that have the
same goal. External search is the process of collecting information which aim to explore the existing
information about competitors' products. Benchmarking carried out on the product Crane Scale
Metrology MT2000 series and Kenkko KK-300H. This product is used as a benchmark because of
the features of this product is very diverse.
Description Function
Hanging scales will be designed that when palm oil was weighed, number of weighing results
will appear and then weighing results will be stored into the data logger along with the location of
weighing defined by the GPS module. Data will be stored until the weighing has been done up to 1
batch. 1 batch consists of several times the weighting that will be adjusted to cluster the plantation
itself. After weighing up to 1 batch, then the weighing data and location coordinates will be sent via
GSM module to the management computer. This cycle will be repeated until the weighing is
completed. And after the completion of all the data that has been in the record, hanging scales will
send the number of times the weighing is done.
Start
Weigh Palm
no
The numbers
weighing appears in
the display
Batch X sent
no
Weighing data is
stored in the logger
yes
Data bacth X
received
Total weighing
already one batch?
Weigh last batch ?
yes
Finish
Fig. 2 Description Function
Morphological Chart
After getting quite a lot of ideas for the design concepts, the ideas will be collected into a
morphological chart for the combined. Morphological chart is a list or summary of the analysis of the
changes in a systematic form to find out how the shape of the product is made.
Alternative
No
Function
I
II
III
1
Scales Form
Fused
Separate
2
Display
LCD
LED
3
Data Sending
GSM Signal
Wifi Signal
4
Data Storage
Raspberry Pi
Data Logger
5
Capacity of Memory
512Mb
1Gb
2Gb
6
Battery T ype
Rechargeable
Nonrechargeable
Built-In/Internal Rechargeable
7
Combining Port
Port RS 232
Direct Communication
USB
8
Define Location
Modul GPS
Fig. 3 Morphological Chart
Concept Selection
The selection concept which will come out to be the best solution, there are two steps that must be
performed for screening and assessment concepts. Filtering concept is that the evaluation process is
approximate aiming to narrow the alternatives. The concept selection is a concept analysis to select
one of the concepts that allow to bring success to a product.
Filtering Concept
Selection matrix is used for filtering concept. The criteria that will be used is taken from the
customer's needs and also judgment of the research team. To perform filtering concept, which
previously had to be determined concepts that will be used as a reference. The concept will be used
as a reference is the concept II.
Table 3 Filtering Concept
Selection Criteria
I
+
+
+
0
3
1
1
2
2
Ease to be made
Portability
Ease of maintenance
Capacity data storage
efficiency
Sum +
Sum 0
Sum Final Score
Rank
II
0
0
0
0
0
0
5
0
0
3
Alternative Concept
III
0
+
+
+
+
4
1
0
4
1
IV
0
0
0
0
3
2
-2
4
V
0
0
0
2
3
-3
5
Assessment Concept
After filtering concept, obtained three concepts that are considered the most good. Of the three
existing concepts will be assessed with weighted criteria aimed to select the best concept.
Determination of criteria weights are determined by consideration of the opinion research team
consumer needs.
Table 4 Assesment Concept
Weighted Criteria
Selection Criteria
Weight
Ease to be made
25%
Portability
25%
Ease of maintenance
25%
Capacity data storage
10%
efficiency
15%
final score
rank
I
Rating Score
4
1
4
1
4
1
2
0,2
3
0,45
3,65
2
Concept fIltered
II
Rating Score
3
0,75
3
0,75
3
0,75
3
0,3
3
0,45
3
3
III
Rating
3
4
5
4
4
4
1
Score
0,75
1
1,25
0,4
0,6
Achitecture Product
Product architecture is functional assignment elements of the product to a collection of buildings
(physical building blocks) [9]. The purpose of the product architecture is outlining the basic physical
components of a product, the function of the components in the product and the relationship of each
component in the architecture phase of the product, there are several steps that need to be done is to
make the scheme of products and grouping elements contained in the scheme products. The following
explanation of the stages of product architecture that has been done
Product Scheme
Once the best solution concept has been established, then the concept converted into a scheme that
functions more detail. The scheme will be described in the block diagrams and flow charts function.
Energy Flow
Signal / Data Flow
Load Cell
LCD Display
Analog To Digital
Converter
(ADC)
Microcontroller
Power Supply
GSM Module
Data Logger
GPS Module
Fig. 3 Product Scheme
The main components of this tool is the load cell. The function of the size of the load cell to convert
weight into electrical voltage. The output of the load cell in the form of electrical voltage which will
be transferred to the analog to digital converter for conversion of voltage into a digital signal that can
be processed in the microcontroller. From the data microcontroller weighing results already in the
form of a digital signal in the display to the LCD display. Once the data is weighing results are stored
in the data logger along with location data that is defined by weighing the GPS module. After
weighing data and location data is collected weighing, GSM module will send data to the management
computer that has been prepared short messages service gateway.
Summary
The design concept of digital-based weighting to oil palm plantations has been done by generating a
concept proposal is an alternative design concept 3 to form these scales will be made incorporated
with the LCD screen displays. Data transmission will use the GSM signal. Data storage media will
be using the data logger with a capacity of 2GB. The battery will be used to recharge. For additional
connection module using direct communication without using the port. While to define the location
of weighing keep using the GPS module. The design concept has a function that can store data of
weighing results into a data logger and send data through the weighing result of the GSM signal. The
concept is also possible to define the location coordinates weighing using GPS module so that
management can determine where the weighing is done.
References
[1] D.I. Maryanie, W. Sutopo, and Yuniaristanto: A Holistic Feasiblilty Study Framework to
Determine Valueable Chain in Palm Oil Industry, Proceedings of The World Congress on
Engineering, Vol .1, London, U.K. (2013)
[2] The Ministry of Coordinating Economic Affairs the Republic of Indonesia, The Master Plan For
Acceleration And Expansion On Indonesian’s Economic Development (MP3EI), The Ministry of
Coordinating Economic Affairs the Republic of Indonesia, Jakarta (2011)
[3] United States Department of Agriculture, Palm Oil Productions Growth to continue, Indonesia
2009
[4] Serikat Petani Kelapa Sawit Sanggau, Fulfill Companies’ Commitment to Respect Human Rights
and Best Practices for Indigenuous Peoples, Farmers and Labourers (2010)
[5] H. Norihan,Mail an den Verfasser vom15.9 (2010)
[6] United States Department of Agriculture, Oilseeds : World Market and Trade, Circular Series
FOP , 2010
[7] Toepfer International, Statistical Information About The Grain and Feedstuff Market, (2009)
[8] Informtion on http://www.bisnis.com
[9] Ulrich & Eppinger, 2001
Pringgo W. Laksono 1,a, Roni Zakaria 1,b, Pandu S. Nugroho1,c
1
Department of Industrial Engineering, Faculty of Engineering, Sebelas Maret Unversity Surakarta,
Indonesia
a
b
pringgo@ft.uns.ac.id, 2012.ibnu@gmail.com, cpandusandito@gmail.com
Keywords: consumer requirements, concepts design, digital hanging scales, morphological chart, weighted
criteria, palm oil scale
Abstract. Indonesia produces about 44% of world’s palm oil. This is supported by the palm
plantation area owned by Indonesia reached 9.2 million hectares, or twice as large as Malaysian palm
oil. With large oil palm area, controlling process will be difficult to do and causing the chance of
weighing data manipulation which make a loss for stakeholders of oil palm plantations. To minimize
the chances of weighing data manipulation, this research aims to generate design of digital scale
according to the needs of stakeholders in the oil palm plantations. Based on consumer requirement,
this research has generated several concepts are combined with morphological chart. By using
weighted criteria, a design of digital scale has selected from several concepts. This study also
complements the selected concept by the architecture design, which aims to describe the physical and
functions of the components of the product and also the relationship between the components. The
final design makes the digital scale capable to send weighing data and location using GSM module,
which can minimize the possibility of weighing data manipulation.
Introduction
Indonesia produces about 44% to 47% of palm oil production worldwide [1, 2]. One of the factors
that make Indonesia able to dominate the world market of palm oil is the palm plantations owned by
Indonesia is very large, which is estimated at around 9.2 million hectares, or twice the area of land
owned by Malaysia [2 – 5]. In the other hand, the productivity of the Indonesian palm plantations is
still low because the land is owned by Indonesia reaches twice the land area of Malaysia but the
number of total production was only about 2 million tons of production [6, 7].
With a very large plantations, Indonesia should have accurate data about the productivity of the land
to determine the policies relating to the stability of the need for renewable energy supply. In fact,
there are still problems in the management of oil palm harvesting of data that is the weighing data
manipulation lands production of palm oil. PTPN V identifies a decrease in the production of palm
oil between 15-20 tons per day or lose a profit of 60 billion per year as a result of weighing data
manipulation [8]. The data manipulation performed by the interpreter weigh indicated by reducing
the weighing results of actual data. It reduces the income that land managers will lower interest land
managers in managing oil palm land that would adversely affect the efforts to maintain the
productivity of oil palm land.
Currently palm plantation in Indonesia is generally managed by a third party, are PTPN (State),
processing plants (Private), and civil society groups. Land management, especially in the weighing
process is still done manually with less supervision. With this kind of process weighing, weighing
data manipulation is still very possible to do so that the mechanism which can reduce the possibility
of manipulation of weighing data. This study intends to create a mechanism that can prevent the
manipulation of weighing data.
Methodology
This research was conducted with approaches as shown as by Fig. 1. First step of this research is
identify costumers requirements. Customer requirements obtained from interviews with the owners
of oil palm plantation. There are 10 owners of oil palm plantation who became respondents. Customer
requirement is converted into a technical solution for the preparation of the draft. Technical solution
obtained with the focus group discussion by experts. In addition, also conducted benchmarking with
competitors' products. Once arranged several concepts, it will be filtered and made an assessment of
the concept. After getting the results will be made product scheme
Start
Product
Planning
Problem
Identification
Collecting Data
Processing
Data
Analysis
·
·
Identify Customer Needs
Collecting customer needs
Interpretation Customer Needs
·
·
·
Preparation of concept
External and Internal search
Product Function Description
Morphological Chart
·
·
Concept Selection
Filtering concept
Assessment concept
·
·
Product Architecture
Product scheme
Grouping Elements Products
Analysis
Conclusions
Conclusions
Finish
Fig.1 Methodology
Result and Discussions
First step of this research is identify costumers requirements. Customer requirements obtained
from interviews with the owners of oil palm plantation. Customer requirement is converted into a
technical solution to generate several alternatives concept. By using weighted criteria, a design of
digital scale has selected from several concepts. After the concept has selected, this study continued
and finished by architecture design of digital hanging scale.
Identify Costumer Needs
Identify customer needs done by organizing focus group discussions with researchers and
interviewed consumers who use hanging scales. Customers who responded to the interview is the
consumers who use hanging scales for plantations. The result of costumer requirement is shown at
Table 1.
Table 1 Costumer Requirements
No.
1
2
3
4
5
6
7
8
9
10
Costumer Requirements
I want to look back on weighing has been done
Can be integrated with computer
I want the operator does not need to record the weighing results
I want the operator can not play the numbers hasi weighing
Hanging scales must be waterproof
Hanging scales do not have to frequently replace the battery
Hanging scales should be easy to use so the operator does not need to learn more
Scales used must be durable
It would be easier if you do not need to replace the battery
I need to know the weighing being performed
Concept Preparation
Conceptualization stage will be divided into four steps, namely are internal and external searches,
description of the function of the product, and morphological chart. Here are the stages of
Conceptualization.
Internal search
The Internal search conducted to extend the ideas to find a solution of the identification of
customer needs. Internal search conducted by a discussion with the parties within the team
environment.
Table 2 Internal Search
No
Costumer Requirement
Technical Solutions
1
2
3
4
5
6
7
8
9
10
I want to look back on weighing has been done
Can be integrated with computer
I want the operator does not need to record the weighing results
I want the operator can not play the numbers hasi weighing
Hanging scales must be waterproof
Hanging scales do not have to frequently replace the battery
Hanging scales should be easy to use
Scales used must be durable
It would be easier if you do not need to replace the battery
I need to know the weighing being performed
Weighing data can be stored and recalled
Using a USB or RS232 port
Weighing data directly sent to the management computer via gsm
Weighing data directly sent to the management computer via gsm
tool material made of waterproof material
Battery capacity is increased or using an internal battery
Simple interface (just turn on the switch and instantly ready for use)
strong casing material selection
Used internal battery
Added GPS module to define the location of the weighing
External search
External search as well as benchmarking with competitors' products or products that have the
same goal. External search is the process of collecting information which aim to explore the existing
information about competitors' products. Benchmarking carried out on the product Crane Scale
Metrology MT2000 series and Kenkko KK-300H. This product is used as a benchmark because of
the features of this product is very diverse.
Description Function
Hanging scales will be designed that when palm oil was weighed, number of weighing results
will appear and then weighing results will be stored into the data logger along with the location of
weighing defined by the GPS module. Data will be stored until the weighing has been done up to 1
batch. 1 batch consists of several times the weighting that will be adjusted to cluster the plantation
itself. After weighing up to 1 batch, then the weighing data and location coordinates will be sent via
GSM module to the management computer. This cycle will be repeated until the weighing is
completed. And after the completion of all the data that has been in the record, hanging scales will
send the number of times the weighing is done.
Start
Weigh Palm
no
The numbers
weighing appears in
the display
Batch X sent
no
Weighing data is
stored in the logger
yes
Data bacth X
received
Total weighing
already one batch?
Weigh last batch ?
yes
Finish
Fig. 2 Description Function
Morphological Chart
After getting quite a lot of ideas for the design concepts, the ideas will be collected into a
morphological chart for the combined. Morphological chart is a list or summary of the analysis of the
changes in a systematic form to find out how the shape of the product is made.
Alternative
No
Function
I
II
III
1
Scales Form
Fused
Separate
2
Display
LCD
LED
3
Data Sending
GSM Signal
Wifi Signal
4
Data Storage
Raspberry Pi
Data Logger
5
Capacity of Memory
512Mb
1Gb
2Gb
6
Battery T ype
Rechargeable
Nonrechargeable
Built-In/Internal Rechargeable
7
Combining Port
Port RS 232
Direct Communication
USB
8
Define Location
Modul GPS
Fig. 3 Morphological Chart
Concept Selection
The selection concept which will come out to be the best solution, there are two steps that must be
performed for screening and assessment concepts. Filtering concept is that the evaluation process is
approximate aiming to narrow the alternatives. The concept selection is a concept analysis to select
one of the concepts that allow to bring success to a product.
Filtering Concept
Selection matrix is used for filtering concept. The criteria that will be used is taken from the
customer's needs and also judgment of the research team. To perform filtering concept, which
previously had to be determined concepts that will be used as a reference. The concept will be used
as a reference is the concept II.
Table 3 Filtering Concept
Selection Criteria
I
+
+
+
0
3
1
1
2
2
Ease to be made
Portability
Ease of maintenance
Capacity data storage
efficiency
Sum +
Sum 0
Sum Final Score
Rank
II
0
0
0
0
0
0
5
0
0
3
Alternative Concept
III
0
+
+
+
+
4
1
0
4
1
IV
0
0
0
0
3
2
-2
4
V
0
0
0
2
3
-3
5
Assessment Concept
After filtering concept, obtained three concepts that are considered the most good. Of the three
existing concepts will be assessed with weighted criteria aimed to select the best concept.
Determination of criteria weights are determined by consideration of the opinion research team
consumer needs.
Table 4 Assesment Concept
Weighted Criteria
Selection Criteria
Weight
Ease to be made
25%
Portability
25%
Ease of maintenance
25%
Capacity data storage
10%
efficiency
15%
final score
rank
I
Rating Score
4
1
4
1
4
1
2
0,2
3
0,45
3,65
2
Concept fIltered
II
Rating Score
3
0,75
3
0,75
3
0,75
3
0,3
3
0,45
3
3
III
Rating
3
4
5
4
4
4
1
Score
0,75
1
1,25
0,4
0,6
Achitecture Product
Product architecture is functional assignment elements of the product to a collection of buildings
(physical building blocks) [9]. The purpose of the product architecture is outlining the basic physical
components of a product, the function of the components in the product and the relationship of each
component in the architecture phase of the product, there are several steps that need to be done is to
make the scheme of products and grouping elements contained in the scheme products. The following
explanation of the stages of product architecture that has been done
Product Scheme
Once the best solution concept has been established, then the concept converted into a scheme that
functions more detail. The scheme will be described in the block diagrams and flow charts function.
Energy Flow
Signal / Data Flow
Load Cell
LCD Display
Analog To Digital
Converter
(ADC)
Microcontroller
Power Supply
GSM Module
Data Logger
GPS Module
Fig. 3 Product Scheme
The main components of this tool is the load cell. The function of the size of the load cell to convert
weight into electrical voltage. The output of the load cell in the form of electrical voltage which will
be transferred to the analog to digital converter for conversion of voltage into a digital signal that can
be processed in the microcontroller. From the data microcontroller weighing results already in the
form of a digital signal in the display to the LCD display. Once the data is weighing results are stored
in the data logger along with location data that is defined by weighing the GPS module. After
weighing data and location data is collected weighing, GSM module will send data to the management
computer that has been prepared short messages service gateway.
Summary
The design concept of digital-based weighting to oil palm plantations has been done by generating a
concept proposal is an alternative design concept 3 to form these scales will be made incorporated
with the LCD screen displays. Data transmission will use the GSM signal. Data storage media will
be using the data logger with a capacity of 2GB. The battery will be used to recharge. For additional
connection module using direct communication without using the port. While to define the location
of weighing keep using the GPS module. The design concept has a function that can store data of
weighing results into a data logger and send data through the weighing result of the GSM signal. The
concept is also possible to define the location coordinates weighing using GPS module so that
management can determine where the weighing is done.
References
[1] D.I. Maryanie, W. Sutopo, and Yuniaristanto: A Holistic Feasiblilty Study Framework to
Determine Valueable Chain in Palm Oil Industry, Proceedings of The World Congress on
Engineering, Vol .1, London, U.K. (2013)
[2] The Ministry of Coordinating Economic Affairs the Republic of Indonesia, The Master Plan For
Acceleration And Expansion On Indonesian’s Economic Development (MP3EI), The Ministry of
Coordinating Economic Affairs the Republic of Indonesia, Jakarta (2011)
[3] United States Department of Agriculture, Palm Oil Productions Growth to continue, Indonesia
2009
[4] Serikat Petani Kelapa Sawit Sanggau, Fulfill Companies’ Commitment to Respect Human Rights
and Best Practices for Indigenuous Peoples, Farmers and Labourers (2010)
[5] H. Norihan,Mail an den Verfasser vom15.9 (2010)
[6] United States Department of Agriculture, Oilseeds : World Market and Trade, Circular Series
FOP , 2010
[7] Toepfer International, Statistical Information About The Grain and Feedstuff Market, (2009)
[8] Informtion on http://www.bisnis.com
[9] Ulrich & Eppinger, 2001