To safeguard the livelihood of consumers, food producers are required, either by law or regulator... more To safeguard the livelihood of consumers, food producers are required, either by law or regulatory bodies, to inspect their products for quality before selling the products to consumers. This is because food processing, as is the case with most production systems, is not perfect and there is a possibility that some of the processed products do not meet the required quality standard. Likewise, the inspection process is seldom perfect, meaning that it is subject to errors and thus, some of the processed products might be incorrectly classified. In light of this, an inventory model for a four-echelon food processing supply chain is developed. The supply chain has a farming echelon where live items are grown with the possibility that some of them might not survive; a processing echelon where the live items are transformed into processed inventory; an inspection echelon where the processed inventory is classified into good and poorer quality classes under the assumption that the inspecti...
International Journal of Quality & Reliability Management
PurposeThis research aims to examine the complementary impact of Lean Manufacturing (LM) and Gree... more PurposeThis research aims to examine the complementary impact of Lean Manufacturing (LM) and Green Manufacturing (GM) on operational and environmental performance.Design/methodology/approachA survey was conducted in the Zimbabwean manufacturing industry. AÂ total of 302 valid responses were obtained and analysed using partial least square structural equation modelling (PLS-SEM).FindingsBoth LM and GM impact environmental and operational performance; however, GM's effect on operational performance is indirect through environmental performance.Research limitations/implicationsThis study only focusses on the Zimbabwean manufacturing industry, and the results may not readily apply to other developing countries.Practical implicationsThe companies that have successfully implemented LM are able to implement GM more easily because of their complementary nature.Social implicationsThe integration of LM and GM reduces most forms of waste, causing an improved environmental and operational pe...
Modelling and Simulation / 687: Health Informatics, 2010
OPTIMISING FLOW IN AN M/M/1 SYSTEM WITH SHORTAGE COST: A THEORY OF CONSTRAINTS APPROACH Olufemi A... more OPTIMISING FLOW IN AN M/M/1 SYSTEM WITH SHORTAGE COST: A THEORY OF CONSTRAINTS APPROACH Olufemi Adetunji and VSS Yadavalli* Department of Industrial and Systems Engineering, University of Pretoria Pretoria 0002 South Africa Olufemi.adetunji@up. ...
In this paper, a three-item EOQ model is proposed, where Product 1 is the main item and has a dem... more In this paper, a three-item EOQ model is proposed, where Product 1 is the main item and has a demand that is dependent on the following: its selling price and stock level, the selling price of the mutual complement (Product 2), selling price of its substitute (Product 3), and time. Product 2 has a demand that is dependent on its selling price, the selling price of its complement (Product 1) and time. Product 3 has a demand that is dependent on its selling price, the selling price of its substitute (Product 1) and time. A practical scenario for this model is in the perishable chicken feed supply chain between the supplier of medicines used in chicken feed production and a manufacturer of animal feed. Typical in this node of the supply chain the manufacturer of animal feed may source various medications from the same supplier. Due to certain nutritional specification of the feed formula, some of these medicines must be used together (complementarily), while some of these medicines can...
2022 IEEE IFEES World Engineering Education Forum - Global Engineering Deans Council (WEEF-GEDC), 2022
Engineering training should prepare students for
industry work; hence, it is expected that the a... more Engineering training should prepare students for
industry work; hence, it is expected that the academic curriculum
should be structured after the requirements of the industry. The
objective of this research was to understand what Industrial
Engineering (IE) skills are used in the industry by the university
students during their vacation work. This may help in determining
the level of emphasis placed on some of the skills with which students
are imbued, and how soon the exposure to these skills should be
during the training period.
It was found out that the mostly used skills are the soft skills, and
not the technical engineering skills imparted into the students.
Moreover, even among the engineering skills used, most students
make more extensive use of the basic engineering skills acquired
earlier in their study years than the more advanced skills taught
later in the Universities.
The study indicates that it is important that the training of
engineering students should place sufficient emphasis on teaching
students on team dynamics and relationship management as this
may be more central to their career, especially as they transition
from student to working life.
International Journal of Mathematical, Engineering and Management Sciences
Conventional production systems assume that during the manufacturing processes, machines operate ... more Conventional production systems assume that during the manufacturing processes, machines operate without breakdown over an infinite planning horizon and manufacture only products of good quality. Imperfect production processes as a result of machine degradation are common in manufacturing. This paper deals with a problem that concerns the modelling and evaluation of the performance of a multi-state production system that is subject to degradation and its effect on lot sizing. Here, we consider that the cycle starts with a particular production rate until a point when the inventory reaches a certain level after which the failure mode is activated due to the deterioration of certain components, leading to a reduction in the production rate in order to ensure the continuity of supply until the maximum inventory level is reached. Production then stops to restore the machine and the cycle starts again. We have assumed that the rate at which inventory deteriorates is exponential and that ...
The paper is aimed at developing a model to measure the impact of Lean manufacturing deployment o... more The paper is aimed at developing a model to measure the impact of Lean manufacturing deployment on organizational performance. The model will help industry practitioners to assess the impact of implementing Lean constructs on organizational performance. It will also harmonize the measurement models of Lean performance with the house of Lean that seems to have become the industry standard. The sheer number of measurement models for impact assessment of Lean implementation makes it difficult for new adopters to select an appropriate assessment model or deployment methodology. A literature review is conducted to classify the Lean performance model. Pareto analysis is used to select the Lean constructs for the development of the model. The model is further formalized through the use of Structural Equation Modeling (SEM) in defining the underlying latent structure of a Lean system. An impact assessment measurement model developed can be used to measure Lean performance and can be adopted...
The paper is aimed at developing a model to measure the impact of Lean manufacturing deployment o... more The paper is aimed at developing a model to measure the impact of Lean manufacturing deployment on organizational performance. The model will help industry practitioners to assess the impact of implementing Lean constructs on organizational performance. It will also harmonize the measurement models of Lean performance with the house of Lean that seems to have become the industry standard. The sheer number of measurement models for impact assessment of Lean implementation makes it difficult for new adopters to select an appropriate assessment model or deployment methodology. A literature review is conducted to classify the Lean performance model. Pareto analysis is used to select the Lean constructs for the development of the model. The model is further formalized through the use of Structural Equation Modeling (SEM) in defining the underlying latent structure of a Lean system. An impact assessment measurement model developed can be used to measure Lean performance and can be adopted...
In this paper, we propose a Hybrid Algorithm (HA) to solve the Fixed Charge Solid Location and Tr... more In this paper, we propose a Hybrid Algorithm (HA) to solve the Fixed Charge Solid Location and Transportation problem (FCSLTP). The FCSLTP considers the cost of facility location and route fixed costs during transportation planning or load consolidation. The HA integrates two heuristics into the Genetic Algorithm framework to solve the FCSLTP. Genetic operations are used to select the best combination of facility locations while a greedy heuristic which uses some cost relaxations are used for the initial load allocation. An improvement heuristic, a modified stepping stone method, is then used to consolidate load allocations to realize further possible cost savings. Parameters used for the genetic operations were decided through preliminary studies. Computational studies using randomly generated data were performed to compare the HA solutions with the solutions obtained using CPLEX, a commercial solver. Performance comparison was done based on the quality of solution and computing ti...
This paper presents an algorithm that that can be used in a pull production environment for incre... more This paper presents an algorithm that that can be used in a pull production environment for increasing the product mix through reduced lot sizing while at the same time minimising the system inventory holding cost. Such pull system could be governed by the ...
To safeguard the livelihood of consumers, food producers are required, either by law or regulator... more To safeguard the livelihood of consumers, food producers are required, either by law or regulatory bodies, to inspect their products for quality before selling the products to consumers. This is because food processing, as is the case with most production systems, is not perfect and there is a possibility that some of the processed products do not meet the required quality standard. Likewise, the inspection process is seldom perfect, meaning that it is subject to errors and thus, some of the processed products might be incorrectly classified. In light of this, an inventory model for a four-echelon food processing supply chain is developed. The supply chain has a farming echelon where live items are grown with the possibility that some of them might not survive; a processing echelon where the live items are transformed into processed inventory; an inspection echelon where the processed inventory is classified into good and poorer quality classes under the assumption that the inspecti...
International Journal of Quality & Reliability Management
PurposeThis research aims to examine the complementary impact of Lean Manufacturing (LM) and Gree... more PurposeThis research aims to examine the complementary impact of Lean Manufacturing (LM) and Green Manufacturing (GM) on operational and environmental performance.Design/methodology/approachA survey was conducted in the Zimbabwean manufacturing industry. AÂ total of 302 valid responses were obtained and analysed using partial least square structural equation modelling (PLS-SEM).FindingsBoth LM and GM impact environmental and operational performance; however, GM's effect on operational performance is indirect through environmental performance.Research limitations/implicationsThis study only focusses on the Zimbabwean manufacturing industry, and the results may not readily apply to other developing countries.Practical implicationsThe companies that have successfully implemented LM are able to implement GM more easily because of their complementary nature.Social implicationsThe integration of LM and GM reduces most forms of waste, causing an improved environmental and operational pe...
Modelling and Simulation / 687: Health Informatics, 2010
OPTIMISING FLOW IN AN M/M/1 SYSTEM WITH SHORTAGE COST: A THEORY OF CONSTRAINTS APPROACH Olufemi A... more OPTIMISING FLOW IN AN M/M/1 SYSTEM WITH SHORTAGE COST: A THEORY OF CONSTRAINTS APPROACH Olufemi Adetunji and VSS Yadavalli* Department of Industrial and Systems Engineering, University of Pretoria Pretoria 0002 South Africa Olufemi.adetunji@up. ...
In this paper, a three-item EOQ model is proposed, where Product 1 is the main item and has a dem... more In this paper, a three-item EOQ model is proposed, where Product 1 is the main item and has a demand that is dependent on the following: its selling price and stock level, the selling price of the mutual complement (Product 2), selling price of its substitute (Product 3), and time. Product 2 has a demand that is dependent on its selling price, the selling price of its complement (Product 1) and time. Product 3 has a demand that is dependent on its selling price, the selling price of its substitute (Product 1) and time. A practical scenario for this model is in the perishable chicken feed supply chain between the supplier of medicines used in chicken feed production and a manufacturer of animal feed. Typical in this node of the supply chain the manufacturer of animal feed may source various medications from the same supplier. Due to certain nutritional specification of the feed formula, some of these medicines must be used together (complementarily), while some of these medicines can...
2022 IEEE IFEES World Engineering Education Forum - Global Engineering Deans Council (WEEF-GEDC), 2022
Engineering training should prepare students for
industry work; hence, it is expected that the a... more Engineering training should prepare students for
industry work; hence, it is expected that the academic curriculum
should be structured after the requirements of the industry. The
objective of this research was to understand what Industrial
Engineering (IE) skills are used in the industry by the university
students during their vacation work. This may help in determining
the level of emphasis placed on some of the skills with which students
are imbued, and how soon the exposure to these skills should be
during the training period.
It was found out that the mostly used skills are the soft skills, and
not the technical engineering skills imparted into the students.
Moreover, even among the engineering skills used, most students
make more extensive use of the basic engineering skills acquired
earlier in their study years than the more advanced skills taught
later in the Universities.
The study indicates that it is important that the training of
engineering students should place sufficient emphasis on teaching
students on team dynamics and relationship management as this
may be more central to their career, especially as they transition
from student to working life.
International Journal of Mathematical, Engineering and Management Sciences
Conventional production systems assume that during the manufacturing processes, machines operate ... more Conventional production systems assume that during the manufacturing processes, machines operate without breakdown over an infinite planning horizon and manufacture only products of good quality. Imperfect production processes as a result of machine degradation are common in manufacturing. This paper deals with a problem that concerns the modelling and evaluation of the performance of a multi-state production system that is subject to degradation and its effect on lot sizing. Here, we consider that the cycle starts with a particular production rate until a point when the inventory reaches a certain level after which the failure mode is activated due to the deterioration of certain components, leading to a reduction in the production rate in order to ensure the continuity of supply until the maximum inventory level is reached. Production then stops to restore the machine and the cycle starts again. We have assumed that the rate at which inventory deteriorates is exponential and that ...
The paper is aimed at developing a model to measure the impact of Lean manufacturing deployment o... more The paper is aimed at developing a model to measure the impact of Lean manufacturing deployment on organizational performance. The model will help industry practitioners to assess the impact of implementing Lean constructs on organizational performance. It will also harmonize the measurement models of Lean performance with the house of Lean that seems to have become the industry standard. The sheer number of measurement models for impact assessment of Lean implementation makes it difficult for new adopters to select an appropriate assessment model or deployment methodology. A literature review is conducted to classify the Lean performance model. Pareto analysis is used to select the Lean constructs for the development of the model. The model is further formalized through the use of Structural Equation Modeling (SEM) in defining the underlying latent structure of a Lean system. An impact assessment measurement model developed can be used to measure Lean performance and can be adopted...
The paper is aimed at developing a model to measure the impact of Lean manufacturing deployment o... more The paper is aimed at developing a model to measure the impact of Lean manufacturing deployment on organizational performance. The model will help industry practitioners to assess the impact of implementing Lean constructs on organizational performance. It will also harmonize the measurement models of Lean performance with the house of Lean that seems to have become the industry standard. The sheer number of measurement models for impact assessment of Lean implementation makes it difficult for new adopters to select an appropriate assessment model or deployment methodology. A literature review is conducted to classify the Lean performance model. Pareto analysis is used to select the Lean constructs for the development of the model. The model is further formalized through the use of Structural Equation Modeling (SEM) in defining the underlying latent structure of a Lean system. An impact assessment measurement model developed can be used to measure Lean performance and can be adopted...
In this paper, we propose a Hybrid Algorithm (HA) to solve the Fixed Charge Solid Location and Tr... more In this paper, we propose a Hybrid Algorithm (HA) to solve the Fixed Charge Solid Location and Transportation problem (FCSLTP). The FCSLTP considers the cost of facility location and route fixed costs during transportation planning or load consolidation. The HA integrates two heuristics into the Genetic Algorithm framework to solve the FCSLTP. Genetic operations are used to select the best combination of facility locations while a greedy heuristic which uses some cost relaxations are used for the initial load allocation. An improvement heuristic, a modified stepping stone method, is then used to consolidate load allocations to realize further possible cost savings. Parameters used for the genetic operations were decided through preliminary studies. Computational studies using randomly generated data were performed to compare the HA solutions with the solutions obtained using CPLEX, a commercial solver. Performance comparison was done based on the quality of solution and computing ti...
This paper presents an algorithm that that can be used in a pull production environment for incre... more This paper presents an algorithm that that can be used in a pull production environment for increasing the product mix through reduced lot sizing while at the same time minimising the system inventory holding cost. Such pull system could be governed by the ...
Uploads
Papers by Olufemi Adetunji
industry work; hence, it is expected that the academic curriculum
should be structured after the requirements of the industry. The
objective of this research was to understand what Industrial
Engineering (IE) skills are used in the industry by the university
students during their vacation work. This may help in determining
the level of emphasis placed on some of the skills with which students
are imbued, and how soon the exposure to these skills should be
during the training period.
It was found out that the mostly used skills are the soft skills, and
not the technical engineering skills imparted into the students.
Moreover, even among the engineering skills used, most students
make more extensive use of the basic engineering skills acquired
earlier in their study years than the more advanced skills taught
later in the Universities.
The study indicates that it is important that the training of
engineering students should place sufficient emphasis on teaching
students on team dynamics and relationship management as this
may be more central to their career, especially as they transition
from student to working life.
industry work; hence, it is expected that the academic curriculum
should be structured after the requirements of the industry. The
objective of this research was to understand what Industrial
Engineering (IE) skills are used in the industry by the university
students during their vacation work. This may help in determining
the level of emphasis placed on some of the skills with which students
are imbued, and how soon the exposure to these skills should be
during the training period.
It was found out that the mostly used skills are the soft skills, and
not the technical engineering skills imparted into the students.
Moreover, even among the engineering skills used, most students
make more extensive use of the basic engineering skills acquired
earlier in their study years than the more advanced skills taught
later in the Universities.
The study indicates that it is important that the training of
engineering students should place sufficient emphasis on teaching
students on team dynamics and relationship management as this
may be more central to their career, especially as they transition
from student to working life.