Rajab Abdullah Hokoma
Faculty of Engineering, University of Tripoli , Libya
E-mail: r.hokoma@uot.edu.ly
Hala Mansour Amaigl
Ministry of Education and Scientific Research, Libya
E-mail: hokoma@hotmail.com
Submission: 30/09/2018
Revision: 29/10/2018
Accept: 06/11/2018
ABSTRACT
This paper investigates in detail the
current status of the implementation levels of JIT key-factors and their
sub-elements within the cement industry within Libya, and its implication for
management within the said industry. A survey methodology has been applied in
this detailed investigation using an intensive questionnaire and one-to-one
interviews of the correspondent organizations. Based on the analysis of the
survey findings, the results show that the implementation status of the JIT
key-factors and their sub-elements are found to be in the modest levels across
all the surveyed organisations, thereby indicating to opportunities for
eliminating waste and improving the value chain. This paper has also pointed to
crucial areas where the senior management body within this industry need to
take immediate actions in order to achieve an effective and successful
implementation of JIT systems. The paper also makes a contribution by providing
an insight into what extent the JIT key-factors and their sub-elements are
understood and implemented within the key Libyan manufacturing industry.
Keywords: JIT; Manufacturing; Industry;
Questionnaire; Implementation; Libya
1. INTRODUCTION
Global competition is posing
challenges and creating opportunities for manufacturing and business companies
to ensure their positions in the marketplace. Improving quality and increasing
customers’ satisfaction can be effectively used to meet these challenges.
Industrial companies as well as academic institutions have paid a considerable
attention to JIT, as a new manufacturing approach, developed for increasing the
value added on the production processes, and reducing the waste to increase
productivity throughout the entire business area (LI-HSING;
WEI-FENG, 2013; HOKOMA,
2016a),
Libya was poor before discovering
the Oil & Gas during 1960’s. after that, the country paid serious attention
towards developing strategies in order to update all areas that could
contribute in improving all the industries across the country (RIFAI et. al.
2006; HOKOMA 2016B; HOKOMA et. al. 2008).
However, Libya faced a lot of major
problems after the country was embargoed by the UN sanctions during the 1990s.
Libya resumed upgrading of its manufacturing industries after the release from
these sanctions in 2001, aiming to achieve the most possible benefits by
implementing the latest techniques in order to improving the current situation
of most industries, including the industry targeted for this study (TUGHAR
et. al., 2007).
2. AN OVERVIEW OF JIT AND ITS KEY-ELEMENTS:
Most manufacturing companies are
trying to implement JIT practices (either partially or fully) in order to
achieve continuous improvement in the overall productivity of their products
and services. This fact has been well
documented in the literature. According to Polat (2005) and Yasutaka (2013), JIT is widely
implemented in areas of manufacturing, production and service systems.
This implementation covers all the
processes and operations used, including all the elements flowing throughout
the entire processes in the whole system and it performed well in reducing the
inventory levels. In the same line, Lai et.
al. (2003) concluded that JIT could be integrated with supply chain
management for product development and inventory reduction in order to reduce
the supply chain costs and build good relationships with suppliers.
The literature search has shown that
there is a quite large amount of research that has been carried out on JIT and
its key-factors, focusing more on their implementation processes along
with considering their main objectives
Henry (1998), Callen and Itzhak (2000), Dong
et. al, (2001), Fullerton and McWatters (2001), Oral and Erdis (2003),
Hokoma et. al. (2006) and Hokoma and Amaigl (2016), pointed out that JIT can be
implemented to produce goods and services that are needed by customers quickly,
safely and economically; to reduce time and cost of material handling by
effective arrangement and utilisation of machines; to eliminate all types of
waste; to improve the performance of the companies; to minimise the sum of the
ordering and set-up times and costs; to compress the lead-time needed for
delivering the products and services; to improve customer service level; to
increase the competitive edge in the business areas; to reduce the uncertainty
in materials demand by linking this with the production plan; to create a stable environment to make JIT
work and to reduce costs by using specialised automation machines.
Furthermore, According to Fulletton
(2001), the executive management involvement and guidance through all the
operations within any company are the main cause of successful implementation
of JIT practices. The key elements of JIT and other related issues that are
considered as crucial for implementing successful JIT system are; Eliminating
Waste, Continuous Improvement Programmes (CIP), Reducing Set-up Time, implementing
Preventative Maintenance Programmes (PMP), Kanban, Levelled/Mixed Scheduling
Programmes and Teamwork Approach Gargeya
(2002),
This paper covers a detailed
investigation of the actual implementation status of JIT and its key-factors
and their sub-elements within the Libyan Cement industry, thereby, developing
their path towards achieving World Class Manufacturing (WCM) status.
3. METHODOLOGY AND DATA COLLECTION:
Questionnaire survey was designed to
ascertain in detail the current implementation status of JIT key-factors and
their sub-elements, which were implemented within the targeted industry. The
sub-elements of JIT, being the core of any effective implementation of JIT,
were also deeply investigated in order to ascertain the extent of these
implementation levels within the surveyed industry. The targeted people for
this survey were the top and senior managers working within the targeted
organisations and involved within key decision making processes.
The questionnaire consists of 11
main questions, with the main questions broken down into 99 sub-questions,
investigating the extent of use and implementation of each of the investigated
JIT key-factors. The respondents were given a choice to indicate their answers
to specify the extent use of each of the given approach or technique using
Likert Scale from 0 (non-implementation) to 6 (full implementation). The
questionnaire was pre-tested through several intensive reviews with academics
and experts conversant with the manufacturing areas, and then was passed to
expert colleagues for a discussion concerning its contents and the expected
level of understanding from the respondents within the targeted industry.
As a first step of distributing the
questionnaire, a formal letter was mailed to all the targeted managers,
providing a general idea about the survey and its contribution in developing
the targeted industry. In the second stage, a total of 800 hard copies of
questionnaire were distributed to the targeted managers working within the
targeted industry including most of the related managers. Each copy of the
questionnaire was accompanied with another letter from the researchers
providing the reasons for conducting this survey and providing contact details
in a case of any inquiries or clarifications are needed. Out of the 800
questionnaire’ copies sent, a total of 520 copies were returned with the
full-completed questionnaires, giving a response rate of 65%.
Complementary to the questionnaire
survey, couple of interviews were carried out between the researchers and
senior managers working within the targeted industry, where information related
to the surveyed industry was provided to the interviewers, and site visits to
seven correspondent cement factories were additionally carried out in order to
collect more knowledge about the manufacturing processes and the working
environment within this industry.
4. DATA ANALYSIS AND DISCUSSION:
A reliability test was conducted for
the entire questionnaire as a first step of analysing the collected data.
Cronbach’s Alpha was used as the Coefficient of Reliability for testing the
internal consistency of the constructs of the entire questionnaire. The
calculated value of Cronbach’s Alpha was found to be 0.792. According to
Pallant (2005), a Cronbach’s Alpha Coefficient of 0.70 or above is considered
adequate for the reliability of the entire questionnaire. Therefore, in this
research 0.792 gives strong evidence that the questionnaire responses were
reliable.
4.1.
Investigating The Implementation Status of Each JIT Key Factor:
The survey tried to ascertain the
implementation status of the JIT key-factors within the Libyan cement industry
in order to provide a detailed picture of the existing JIT environment within
this industry. The findings are summarised and illustrated in Table 1. It shows
that the implementation status of the first two investigated key-factors (implementing
programmes to eliminate waste and implementing continuous improvement
programmes) are affecting the implementation status of the other
key-factors. This is because these two elements are the key-drivers of all the
other related JIT key-factors within this industry.
The table shows that the surveyed
industry is implementing programmes to eliminate waste with 90%. The continuous
improvement programme is found implemented at lower level across the entire
industry. These two key-factors should be fully implemented in order to achieve
effective implementation of the JIT system, whereas in this survey they are
found be practiced at lower implementation levels.
The poorest implementation levels
across the entire surveyed industry as expected are with Group Technology,
Kanban and implementing Levelled/Mixed Scheduling programmes (all
less than 19%) as these elements are not relevant to this industry (more
relevant to batch-size production environments).
These three elements will not be
discussed in detail elsewhere. The table also shows that the Preventative
Maintenance Programmes are well-implemented throughout the entire
industry (above 90%) as in this industry breakdown affects are critical and
need to be avoided. This implementation of PMP programmes requires
multifunctional skills employees which also found to be at high levels of
implementation.
Worryingly, the Total Quality
Management, Quality Circle Programmes and Reducing Set-up Time are
implemented at modest levels, where more attention should be paid in order to
achieve effective and successful implementation of JIT system within the cement
industry. In particular, the overall implementation status of JIT key-factors
within the cement industry is modest across all the investigated categories.
This situation needs immediate and serious actions in order to achieve the
desired benefits of implementing JIT system.
Table
1: The implementation status of the JIT key-factors
|
JIT Key-factor |
Implementation level (%) |
||
|
Yes |
No |
Do Not Know |
|
|
Implemented
programmes to eliminate waste |
90.0 |
10.0 |
00.0 |
|
Implemented
programmes for continuous improvement |
72.7 |
18.2 |
09.1 |
|
Implementing
programmes to reduce set-up times |
45.5 |
45.4 |
09.1 |
|
Implemented
programmes for Group Technology layout |
09.1 |
54.5 |
36.4 |
|
Implemented
levelled/mixed scheduling programmes |
09.1 |
54.5 |
36.4 |
|
Used Kanban
cards/signals as a production control system |
18.2 |
54.5 |
27.3 |
|
Implemented
a multifunctional skills training programme |
72.7 |
00.0 |
27.3 |
|
Implemented
preventative maintenance programmes |
91.0 |
00.0 |
09.0 |
|
Implemented
Total Quality Management programmes |
63.6 |
18.2 |
18.2 |
|
Implemented
Quality Circle programmes |
54.5 |
09.1 |
36.4 |
4.2.
Investigating
The Extent of Each JIT Key-Factor Implementation Levels:
The
implementation status of the JIT key-factors was investigated in detail, broken
down into sub-elements for each of the main questions in order to ascertain the
actual implementation status of each of these key-elements within the surveyed
industry. The calculated mean values of all these sub-elements of the JIT
key-factors are shown in Tables 2 to 8. The key-factor of eliminating the
waste is broken down into 8 sub-elements, which are illustrated along with
their implementation status in Table 2 on a scale of 0 (non-implementation) to
6 (full implementation).
Table
2: The implementation status of eliminating the waste
|
Implementing
programmes to eliminate the waste |
Mean value |
|
Eliminated the waste
due to over production |
3.82 |
|
Eliminated the waste
by reducing the queues and the waiting times |
2.82 |
|
Planned and
controlled the operations avoiding any extra operations |
3.09 |
|
Eliminated the waste
due to delay of materials before processing |
3.18 |
|
Eliminated the waste
due to unnecessary transportation of materials |
3.36 |
|
Eliminated the waste
by reducing the inventory materials |
3.09 |
|
Eliminated the waste
by producing ZERO defects |
3.09 |
|
Eliminated the waste
due to proper utilisation of the employees |
4.00 |
|
Overall
mean value |
3.31 |
Looking
at Table 2, the cement industry is with modest level of implementation of waste
elimination programmes with overall mean values of 3.31. This indicates to
a lot of potential to reduce costs and make the operations more efficient
within each of these sub-elements. This also shows room for improvement.
However, even this indicates to potential cost saving. Table 3 shows the
implementation of sub-elements of continuous improvement. This also
worryingly a very poor implementation as the overall mean values across the
entire industry is 2.85 over 6. On closer inspection on Table 3, the first five
listed sub-elements of continuous improvement show why this is the case.
These
five sub-elements show top management commitment towards implementing the
remaining sub-elements. As can be seen these are mainly below 3, which is very
poor. This then is reflected in the poor implementation in the various
functional areas of the surveyed industry. The programmes implemented to reduce
the set-up times have been investigated in order to assess the extent of this
implementation within the surveyed industry.
Table 3: The
implementation status of the continuous improvement programmes
|
Implementing programmes for Continuous
Improvement Programmes (CIP) |
Mean Value |
|
The top management responded to the
feedback from the employees on JIT/ CIP |
1.73 |
|
Ensuring training programmes for the
management body on JIT/ CIP |
1.45 |
|
Ensuring training programmes to the
administrative staff on JIT/ CIP |
2.91 |
|
The training programmes designed
considering the variety of the employees’ learning needs |
2.82 |
|
Ensuring Continuous Improvement
training programming to the machine operators |
2.45 |
|
Carrying out research and development
to improve the products |
3.00 |
|
Encouraging a continuous improvement
culture within the working environment |
2.73 |
|
Focusing on the requirements of their
customers in designing products |
2.73 |
|
Using team-based approaches to problem
solving |
3.18 |
|
The CIP been implemented in the
Marketing function |
2.82 |
|
The CIP been implemented in the Design
function |
3.45 |
|
The CIP been implemented in the
Production/Manufacturing function |
3.45 |
|
The CIP been implemented in the
Purchasing function |
3.55 |
|
The CIP been implemented in the
Finance function |
3.45 |
|
The CIP been implemented in the
Production Shop Floor function |
2.36 |
|
The CIP been implemented in the
Materials Handling Control function |
3.09 |
|
The CIP been implemented in the
Quality Control function |
4.00 |
|
The CIP been implemented in the
Preventative Maintenance function |
3.82 |
|
The CIP been implemented in the shipping
function |
3.18 |
|
Overall
mean value |
2.85 |
The results are summarised in
Table 4. It shows the sub-elements of set-up time reduction programmes with an
overall mean value of 2.44. Again this table highlights the shortcomings of the
first two sub-elements, which are then effecting the subsequent implementation
of the other sub-elements. A case in point is the low values for implementing
internal and external activities reduction, which indicate to complete lack of
knowledge of this implementation task, no doubt due to the shortcomings
identified for the first two sub-elements in Table 4.
The extent of the implementation
levels of the multi-skilled training programmes is also investigated and the
findings are summarised in Table 5. The table shows that the overall mean
values for the multi-skilled training programmes are relatively higher than the
values in the previous tables. This is a slightly encouraging picture for the
cement industry. However, there is room for improvement, and needs to
drastically address the issue of training staff.
Table 4: The
implementation status of reducing the set-up times programmes
|
Implementing any programmes to reduce set-up
times |
Mean Value |
|
All the employees trained for set-up time
reduction process |
2.36 |
|
The employees trained to perform the set-up
of their machines on time |
2.45 |
|
The operators trained for mounting and
handling items and materials |
2.81 |
|
The operators trained to use the set-up tools |
2.82 |
|
The operators trained to understand and use
the set-up drawings |
2.64 |
|
The operators have sufficient knowledge about
their machines set-ups |
2.82 |
|
The operators have enough skills in improving
set-up times |
2.73 |
|
The set-up time reduction programmes
involving a multifunctional team approach |
2.73 |
|
The relevant teams aware of clear definition
of the set-up times |
2.73 |
|
The relevant teams aware of the distinction
between internal and external set-up activities |
2.64 |
|
The teams converted the internal activities
to external ones by re-examining their true functions |
2.09 |
|
The teams changed as many internal activities
to external activities as possible |
2.36 |
|
The teams actually performed the external
activities as external activities |
1.73 |
|
The teams videotape the changeover and review
for opportunities for improvements |
1.64 |
|
The teams reduce the time needed to perform
internal activities by using quick disconnects |
2.05 |
|
Overall
mean value |
2.44 |
Table 6 illustrates the
implementation status of the Preventative Maintenance Programmes, which found
to be stands at High levels with overall mean value of 3.95. As mentioned
earlier, within this industry any breakdown is critical and thus there is a lot
of investment of resources for preventative maintenance to ensure that no such
breakdowns occur, and leaving much room for improvements in cost savings.
Table
5: The implementation status of the multifunctional skills training programmes
|
Implementing a multifunctional skills training programme |
Mean Value |
|
The
employees receive cross-training programmes |
3.64 |
|
The
employees qualified to perform several different tasks |
3.45 |
|
The
employees qualified to train and/or be trained for their duties |
3.36 |
|
The
employees able to rework the non-conforming items by their own |
3.45 |
|
The
employees inspect the produced items |
3.64 |
|
The
employees maintain the inventory and production control |
4.45 |
|
The
employees qualified to set-up their equipment and tools |
4.18 |
|
The
employees able to execute the minor maintenance needed |
4.64 |
|
Overall mean value |
3.74 |
Tables 7 and 8, show the
detailed investigation results of the implementation status of quality
management programmes within the surveyed industry. The results within Tables 7
and 8 show an extremely worrying picture in that the overall mean values range
from 1.38 (TQM programmes) and to 2.89 for Quality Circle (QC) programmes. The sub-elements contained within both tables
reflect the overall mean values.
Table 6: The
implementation levels of the preventative maintenance programmes
|
Mean Value |
|
|
The
factory has any preventative maintenance system |
4.00 |
|
The
factory keeps records of preventative maintenance schedules |
4.18 |
|
The
factory schedules the planned preventative maintenance |
4.00 |
|
The
preventative maintenance activities scheduled with the main production
programme |
4.19 |
|
The managers
track preventative maintenance programmes |
4.27 |
|
The
maintenance department take the needed actions on time |
4.00 |
|
The
factory keeps records of individuals performing major overhauls |
3.91 |
|
The
operators trained by preventative maintenance people |
3.09 |
|
The
factory keeps records of breakdown frequencies |
4.00 |
|
The
factory keeps records of the repair times |
3.91 |
|
Overall mean value |
3.95 |
Table 7: The
implementation level of the TQM programmes
|
The
factory implemented Total Quality Management programmes |
Mean Value |
|
Implemented any of ISO9000 systems or equivalent |
3.45 |
|
Implemented Statistical Process Control (SPC) |
1.18 |
|
Implemented Quality Function Deployment (QFD) |
0.91 |
|
Implemented Failure Mode and Effect Analysis
(FMEA) |
0.55 |
|
Implemented Experimentation (Taguchi) methods |
0.55 |
|
Overall
mean value |
1.38 |
Table 8: the extent
of the implementation status of the QC programmes
|
The factory implemented any Quality Circle
programmes |
Mean Value |
|
The employees have the authority to stop the
production line due to QC problems |
2.73 |
The employees been organised into
self-directed teams |
2.82 |
|
The employees been able to identify their
operations problems |
3.18 |
|
The employees suggested improvement
programmes |
3.00 |
|
The employees participated in decision-making
process |
2.91 |
|
The employees met to discuss their common
problems |
2.73 |
|
Overall
mean value |
2.89 |
In summary, it seems that the
surveyed industry is not what one could call TQM-centred. This is also the reason why this industry has
not achieved successful JIT implementation, as both JIT and TQM are closely
linked.
5. CONCLUSIONS:
This
is the first study to investigate the detailed actual implementation status of
the JIT and its key-factors and their sub-elements within the cement industry
in Libya. It makes a contribution by providing an insight into what extent
these key-factors are being practiced along with their implication for the
manufacturing and quality operations within this industry. Some key findings
can be summarised as follows:
· The actual implementation status
of JIT practices across the entire surveyed industry is modest because of
unfamiliarity with JIT and some of its key-factors and lack of support from the
executive managers towards this implementation process. The executive managers
within this industry should take serious actions through applying a clear
strategy towards most of the areas that are considered as being crucial in any
effective implementation of the JIT system.
·
The actual implementation status of eliminating the
waste and implementing programmes for continuous improvement programmes (as
the most crucial JIT key-factors) is found to be modest throughout the
entire surveyed industry. In order to achieve effective implementation of the
JIT system, these two key-factors should be fully implemented across the entire
surveyed industry. The key reason for this modest implementation is lack of
support from the senior managers towards this implementation. Again, action is
required by senior managers to overcome these hurdles.
·
Some of the investigated JIT key-factors were found to
be implemented at very poor levels, the reason being that these key-factors are
not related to this industry and are more related to batch-size production
industries.
·
The vision of improving the Libyan cement industry
with respect to JIT could be achieved through setting up employers’ training
and on-going education programmes for all the related individuals and teams in
order to make it easier for local employers and employees.
·
The
survey has also identified difficulties and attitudes that the decision-makers
within industry in general might face towards implementing the JIT system along
with the subsequent key-factors. Therefore, ensuring a high level of
understanding of the whole JIT manufacturing system to all the involved teams
and individuals certainly will lead to an effective implementation of JIT as
manufacturing management system, thereby moving the Libyan industries towards
WCM.
To
summarise, this survey has identified problems faced by the Libyan cement
industry. The findings of this survey have provided insight into the common
problems and shortcomings related to JIT implementation in the surveyed
industry. If JIT implementation is critical to achieve WCM status, then the
findings of this survey can help others considering a conversion to a JIT
system improve the likelihood of a successful JIT implementation.
The
surveyed industry is crucial for Libyan economy. However, this survey has
identified that it needs more attention in terms of JIT implementation and therefore
WCM. In essence, the key reason for this modest status is the lack of the
senior managers’ support towards the implementation process through providing a
high level of awareness about the issue to all the related individuals and
teams.
Finally,
on a positive note, when asked (during one-to-one interviews) about improving
the Libyan cement industry, all the respondents (without any exception) showed
serious willingness and enthusiasm on developing their business areas through
implementing the latest manufacturing management systems in order to achieving
a high level of improvements.
6. ACKNOWLEDGMENT:
This
research is fully supported by the Authority of Natural Science Research and
Technology, Ministry of Education, Tripoli, Libya, with the research project
entitled: Developing JIT/TQM
Model For Its Possible Effective Implementation Within The Libyan Cement
Industry. The authors are grateful to whom they participated and supported this
survey.
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