This paper describes the original Analytic Hierarchy Process (AHP) as it is implemented in the so... more This paper describes the original Analytic Hierarchy Process (AHP) as it is implemented in the software package Expert Choice. We demonstrate its application through a practical example. In particular, we discuss problem modelling, pairwise comparisons, judgement scales, derivation methods, consistency indices, synthesis of the weights and sensitivity analysis. Finally, the limitations of the original AHP along with the new proposed development are explained.
The management of spare parts inventory for maintenance is recognised as offering considerable sc... more The management of spare parts inventory for maintenance is recognised as offering considerable scope for the development of a Computerised Maintenance Management System (CMMS) module. Despite many manufacturers possessing multi-million pound spare parts inventories, little research or analysis has considered how these spares may be better managed and controlled in a practical approach. This is largely because spare parts inventories are notoriously difficult to manage, due to variable and unpredictable demand, erratic lead-times for replenishment and difficulties in determining stockout costs (Sandvig and Allaire, 1998). In this paper, we briefly discuss the maintenance problem. We then examine the role of CMMSs as an aid to address the different challenges facing maintenance especially in terms of management, current deficiencies and spare parts inventories. We focus our investigation on problems with maintenance inventory in terms of conflicting objectives and its unique characteristics. We extend our review to inventory policies and how they relate to maintenance inventory control.
District heating networks are commonly addressed in the literature as one of the most effective s... more District heating networks are commonly addressed in the literature as one of the most effective solutions for decreasing the greenhouse gas emissions from the building sector. These systems require high investments which are returned through the heat sales. Due to the changed climate conditions and building renovation policies, heat demand in the future could decrease, prolonging the investment return period. The main scope of this paper is to assess the feasibility of using the heat demand -outdoor temperature function for heat demand forecast. The district of Alvalade, located in Lisbon (Portugal), was used as a case study. The district is consisted of 665 buildings that vary in both construction period and typology. Three weather scenarios (low, medium, high) and three district renovation scenarios were developed (shallow, intermediate, deep). To estimate the error, obtained heat demand values were compared with results from a dynamic heat demand model, previously developed and validated by the authors. The results showed that when only weather change is considered, the margin of error could be acceptable for some applications (the error in annual demand was lower than 20% for all weather scenarios considered). However, after introducing renovation scenarios, the error value increased up to 59.5% (depending on the weather and renovation scenarios combination considered). The value of slope coefficient increased on average within the range of 3.8% up to 8% per decade, that corresponds to the decrease in the number of heating hours of 22-139h during the heating season (depending on the combination of weather and renovation scenarios considered). On the other hand, function intercept increased for 7.8-12.7% per decade (depending on the coupled scenarios). The values suggested could be used to modify the function parameters for the scenarios considered, and improve the accuracy of heat demand estimations.
This chapter presents industrial revolutions and evolution of manufacturing systems (MSs) and inc... more This chapter presents industrial revolutions and evolution of manufacturing systems (MSs) and includes description of four industrial revolutions (IRs) and the literature survey on conventional MSs with the methodologies and tools used for system design and modelling. It presents definitions of MS concepts from a set of selective references and works, which have influenced on and led to development of the present RMS paradigm. To understand the evolution of MSs aimed at reconfigurability and the position of RMS among conventional MSs, the chapter commences by reviewing industrial revolutions and various types of production systems. Flexible manufacturing systems (FMSs), cellular manufacturing systems (CMSs), agile manufacturing systems (AMSs) and virtual cellular manufacturing systems (VCMS) are described with focusing on the concept, design and modelling aspects. In addition, the need to develop new methodologies aimed at greater flexibility through reconfigurability of MSs is presented.
A hybrid method combining various Reliability (Fault Tree Analysis -FTA-, Reliability Block Diagr... more A hybrid method combining various Reliability (Fault Tree Analysis -FTA-, Reliability Block Diagrams -RBD), Multi Criteria Decision Making (Analytic Hierarchy Process -AHP), High Reliability Organizations (HROs) and Learning from Failures (LFF) framework tools, has been applied to a long-established pattern of small to medium chronic failures in a large Oil & Gas organization. Through the Reliability techniques FTA/RBD, the root causes of the chronic failure pattern were identified, categorized and their interconnections established. The obtained root causes were then used as criteria and with the five principles of mindful organizing as alternatives in constructing the AHP model. Finally, an attempt to extract useful generic lessons from the failure causes identified by applying the learning from failure (LFF) principles was made, in order to obtain guidelines for updating existent company routines. Despite a few shortcomings, some inherent to the tools themselves and some related to the method intent, reasonable results were obtained which appear to demonstrate the applicability of the approach.
The International journal of mechanical engineering education, Oct 1, 2005
The paper describes the design, development, testing and use of a microcontroller- and PC-based c... more The paper describes the design, development, testing and use of a microcontroller- and PC-based control system which was used to repair and enhance an ASEA IRB6 welding robot in the authors' laboratory. The principles described could be applied to any robot of similar age and to provide a low-cost route to revitalise any working robot hardware that is limited by
Centre for Research and Evidence on Security Threats, Sep 1, 2020
This report comprises the findings of CREST funded research into project into making decisions ab... more This report comprises the findings of CREST funded research into project into making decisions about information value. It addresses an important challenge for intelligence analysts. Intelligence analysts are typically required to process large volumes of data in a timely manner in order to extract useful information and detect potential security threats.
Integrated Reconfigurable Manufacturing Systems and Smart Value Chain, 2018
This chapter presents evaluation of economic and operational feasibility of an RMS design as its ... more This chapter presents evaluation of economic and operational feasibility of an RMS design as its first tactical design stage. Because of risk and uncertainty in an RMS environment, this major task must be performed precisely before investment in its detailed design. The feasibility study is not only intended to evaluate the possibility of implementation of an RMS design but also to produce a reference base for its evaluation through the design loop over planning horizons. The RMS key feature of reconfigurability is described as its operational feasibility to deal with capacity changes and functionality, which are considered as the major attributes for feasibility evaluation. An integrated structure of the Analytical Hierarchy Process (AHP) and fuzzy set theory is presented. The fuzzy Analytical Hierarchy Process (FAHP) model is examined in an industrial case study.
This is the second book from A. Dashchenko focussing on "XXI Century Technologies". In ... more This is the second book from A. Dashchenko focussing on "XXI Century Technologies". In this book the problems of theory and practice of development in Reconfigurable Manufacturing Systems and Transformable Factories for various machine-building branches and above all automotive industry are discussed. Problems are studied concerning the development of a new class of production systems which in comparison to the Flexible Manufacturing systems are composed of a far less quantity of machine-tools. In comparison to the conventional automated lines they make it possible to rapidly transform the equipment for new products manufacturing. In 37 chapters more then 50 authors from all over the world discuss the main aspects of the mentioned above problem using their latest scientific and practical achievements.
This paper is based on preliminary research carried out in the development of a model/system for ... more This paper is based on preliminary research carried out in the development of a model/system for prioritisation of organ transplant patient waiting list [Perris, and Labib, 2004]. The intention is to carry out further research in this field. The objectives of the extended research are: i) to investigate the effectiveness of using fuzzy logic in a complex decision-making capacity, in particular, for the prioritisation of kidney transplant recipients and to compare and contrast the performance of a scheme based on fuzzy logic with the actual Kidney Allocation Scheme, ii) to contrast it with another representation and reasoning mechanism applied in the USA based on Multiple Criteria Decision Making (MCDM) techniques, and iii) to develop a self-adaptive feedback model for adjustment of the decision makers' consistency of judgements when setting priorities. Despite the medical research carried out, this paper does not pretend to be an authority on medical decisions. The models can al...
ABSTRACT Tool magazine and automatic tool changer (ATC) are two of the most important key functio... more ABSTRACT Tool magazine and automatic tool changer (ATC) are two of the most important key functional units of the tool reserving and exchanging in machining center, reliability of which directly influences that of the machining centers. Failure analysis is the basic work in reliability analysis. So far, there is little in-depth and meticulous study about failure of the tool magazine and ATC, but there are many problems in the use of tool magazine and ATC. Based on the failure data received from field tracing tests, the failure modes, effects, and criticality analysis of the studied circular tool magazine and ATC are evaluated. The failure positions, causes, and criticalities in circular tool magazine and ATC, which have the highest criticality parameters are explored, offering the basis for the improvement in the design of the new products.
International Journal of Mechanical Engineering Education, 2011
ABSTRACT The paper reports on work carried out on an educational exercise for graduate and underg... more ABSTRACT The paper reports on work carried out on an educational exercise for graduate and undergraduate students that aids the study of Denavit-Hartenberg (DH) programming, through a real application within a ‘learning by doing’ scheme. The work presented to students requires the integration of the motion of an industrial robot (ASEA IRB 6) with a camera vision system (Baxall CD9752); they are asked to develop software that will support: the motion of the robot arm, including forward and reverse kinematics; the detection of an object on a test table; the picking up of the object; and its move to a target position on another test table. To assess the experiment, students select seven random points in the active camera area to determine the difference between the actual location of the end-effector and the location calculated using two methods: the trigonometric solutions and the DH parameters. Students discover that the trigonometric technique gives better position accuracy than DH. The project forms an excellent practical exercise to enhance student learning.
Integrated Reconfigurable Manufacturing Systems and Smart Value Chain, 2018
This chapter presents industrial revolutions and evolution of manufacturing systems (MSs) and inc... more This chapter presents industrial revolutions and evolution of manufacturing systems (MSs) and includes description of four industrial revolutions (IRs) and the literature survey on conventional MSs with the methodologies and tools used for system design and modelling. It presents definitions of MS concepts from a set of selective references and works, which have influenced on and led to development of the present RMS paradigm. To understand the evolution of MSs aimed at reconfigurability and the position of RMS among conventional MSs, the chapter commences by reviewing industrial revolutions and various types of production systems. Flexible manufacturing systems (FMSs), cellular manufacturing systems (CMSs), agile manufacturing systems (AMSs) and virtual cellular manufacturing systems (VCMS) are described with focusing on the concept, design and modelling aspects. In addition, the need to develop new methodologies aimed at greater flexibility through reconfigurability of MSs is presented.
The COVID-19 has placed pandemic modeling at the forefront of the whole world's public policymaki... more The COVID-19 has placed pandemic modeling at the forefront of the whole world's public policymaking. Nonetheless, forecasting and modeling the COVID-19 medical waste with a detoxification center of the COVID-19 medical wastes remains a challenge. This work presents a Fuzzy Inference System to forecast the COVID-19 medical wastes. Then, people are divided into five categories are divided according to the symptoms of the disease into healthy people, suspicious, suspected of mild COVID-19, and suspicious of intense COVID-19. In this regard, a new fuzzy sustainable model for COVID-19 medical waste supply chain network for location and allocation decisions considering waste management is developed for the first time. The main purpose of this paper is to minimize supply chain costs, the environmental impact of medical waste, and to establish detoxification centers and control the social responsibility centers in the COVID-19 outbreak. To show the performance of the suggested model, sensitivity analysis is performed on important parameters. A real case study in Iran/Tehran is suggested to validate the proposed model. Classifying people into different groups, considering sustainability in COVID 19 medical waste supply chain network and examining new artificial intelligence methods based on TS and GOA algorithms are among the contributions of this paper. Results show that the decision-makers should use an FIS to forecast COVID-19 medical waste and employ a detoxification center of the COVID-19 medical wastes to reduce outbreaks of this pandemic.
This paper describes the original Analytic Hierarchy Process (AHP) as it is implemented in the so... more This paper describes the original Analytic Hierarchy Process (AHP) as it is implemented in the software package Expert Choice. We demonstrate its application through a practical example. In particular, we discuss problem modelling, pairwise comparisons, judgement scales, derivation methods, consistency indices, synthesis of the weights and sensitivity analysis. Finally, the limitations of the original AHP along with the new proposed development are explained.
The management of spare parts inventory for maintenance is recognised as offering considerable sc... more The management of spare parts inventory for maintenance is recognised as offering considerable scope for the development of a Computerised Maintenance Management System (CMMS) module. Despite many manufacturers possessing multi-million pound spare parts inventories, little research or analysis has considered how these spares may be better managed and controlled in a practical approach. This is largely because spare parts inventories are notoriously difficult to manage, due to variable and unpredictable demand, erratic lead-times for replenishment and difficulties in determining stockout costs (Sandvig and Allaire, 1998). In this paper, we briefly discuss the maintenance problem. We then examine the role of CMMSs as an aid to address the different challenges facing maintenance especially in terms of management, current deficiencies and spare parts inventories. We focus our investigation on problems with maintenance inventory in terms of conflicting objectives and its unique characteristics. We extend our review to inventory policies and how they relate to maintenance inventory control.
District heating networks are commonly addressed in the literature as one of the most effective s... more District heating networks are commonly addressed in the literature as one of the most effective solutions for decreasing the greenhouse gas emissions from the building sector. These systems require high investments which are returned through the heat sales. Due to the changed climate conditions and building renovation policies, heat demand in the future could decrease, prolonging the investment return period. The main scope of this paper is to assess the feasibility of using the heat demand -outdoor temperature function for heat demand forecast. The district of Alvalade, located in Lisbon (Portugal), was used as a case study. The district is consisted of 665 buildings that vary in both construction period and typology. Three weather scenarios (low, medium, high) and three district renovation scenarios were developed (shallow, intermediate, deep). To estimate the error, obtained heat demand values were compared with results from a dynamic heat demand model, previously developed and validated by the authors. The results showed that when only weather change is considered, the margin of error could be acceptable for some applications (the error in annual demand was lower than 20% for all weather scenarios considered). However, after introducing renovation scenarios, the error value increased up to 59.5% (depending on the weather and renovation scenarios combination considered). The value of slope coefficient increased on average within the range of 3.8% up to 8% per decade, that corresponds to the decrease in the number of heating hours of 22-139h during the heating season (depending on the combination of weather and renovation scenarios considered). On the other hand, function intercept increased for 7.8-12.7% per decade (depending on the coupled scenarios). The values suggested could be used to modify the function parameters for the scenarios considered, and improve the accuracy of heat demand estimations.
This chapter presents industrial revolutions and evolution of manufacturing systems (MSs) and inc... more This chapter presents industrial revolutions and evolution of manufacturing systems (MSs) and includes description of four industrial revolutions (IRs) and the literature survey on conventional MSs with the methodologies and tools used for system design and modelling. It presents definitions of MS concepts from a set of selective references and works, which have influenced on and led to development of the present RMS paradigm. To understand the evolution of MSs aimed at reconfigurability and the position of RMS among conventional MSs, the chapter commences by reviewing industrial revolutions and various types of production systems. Flexible manufacturing systems (FMSs), cellular manufacturing systems (CMSs), agile manufacturing systems (AMSs) and virtual cellular manufacturing systems (VCMS) are described with focusing on the concept, design and modelling aspects. In addition, the need to develop new methodologies aimed at greater flexibility through reconfigurability of MSs is presented.
A hybrid method combining various Reliability (Fault Tree Analysis -FTA-, Reliability Block Diagr... more A hybrid method combining various Reliability (Fault Tree Analysis -FTA-, Reliability Block Diagrams -RBD), Multi Criteria Decision Making (Analytic Hierarchy Process -AHP), High Reliability Organizations (HROs) and Learning from Failures (LFF) framework tools, has been applied to a long-established pattern of small to medium chronic failures in a large Oil & Gas organization. Through the Reliability techniques FTA/RBD, the root causes of the chronic failure pattern were identified, categorized and their interconnections established. The obtained root causes were then used as criteria and with the five principles of mindful organizing as alternatives in constructing the AHP model. Finally, an attempt to extract useful generic lessons from the failure causes identified by applying the learning from failure (LFF) principles was made, in order to obtain guidelines for updating existent company routines. Despite a few shortcomings, some inherent to the tools themselves and some related to the method intent, reasonable results were obtained which appear to demonstrate the applicability of the approach.
The International journal of mechanical engineering education, Oct 1, 2005
The paper describes the design, development, testing and use of a microcontroller- and PC-based c... more The paper describes the design, development, testing and use of a microcontroller- and PC-based control system which was used to repair and enhance an ASEA IRB6 welding robot in the authors' laboratory. The principles described could be applied to any robot of similar age and to provide a low-cost route to revitalise any working robot hardware that is limited by
Centre for Research and Evidence on Security Threats, Sep 1, 2020
This report comprises the findings of CREST funded research into project into making decisions ab... more This report comprises the findings of CREST funded research into project into making decisions about information value. It addresses an important challenge for intelligence analysts. Intelligence analysts are typically required to process large volumes of data in a timely manner in order to extract useful information and detect potential security threats.
Integrated Reconfigurable Manufacturing Systems and Smart Value Chain, 2018
This chapter presents evaluation of economic and operational feasibility of an RMS design as its ... more This chapter presents evaluation of economic and operational feasibility of an RMS design as its first tactical design stage. Because of risk and uncertainty in an RMS environment, this major task must be performed precisely before investment in its detailed design. The feasibility study is not only intended to evaluate the possibility of implementation of an RMS design but also to produce a reference base for its evaluation through the design loop over planning horizons. The RMS key feature of reconfigurability is described as its operational feasibility to deal with capacity changes and functionality, which are considered as the major attributes for feasibility evaluation. An integrated structure of the Analytical Hierarchy Process (AHP) and fuzzy set theory is presented. The fuzzy Analytical Hierarchy Process (FAHP) model is examined in an industrial case study.
This is the second book from A. Dashchenko focussing on "XXI Century Technologies". In ... more This is the second book from A. Dashchenko focussing on "XXI Century Technologies". In this book the problems of theory and practice of development in Reconfigurable Manufacturing Systems and Transformable Factories for various machine-building branches and above all automotive industry are discussed. Problems are studied concerning the development of a new class of production systems which in comparison to the Flexible Manufacturing systems are composed of a far less quantity of machine-tools. In comparison to the conventional automated lines they make it possible to rapidly transform the equipment for new products manufacturing. In 37 chapters more then 50 authors from all over the world discuss the main aspects of the mentioned above problem using their latest scientific and practical achievements.
This paper is based on preliminary research carried out in the development of a model/system for ... more This paper is based on preliminary research carried out in the development of a model/system for prioritisation of organ transplant patient waiting list [Perris, and Labib, 2004]. The intention is to carry out further research in this field. The objectives of the extended research are: i) to investigate the effectiveness of using fuzzy logic in a complex decision-making capacity, in particular, for the prioritisation of kidney transplant recipients and to compare and contrast the performance of a scheme based on fuzzy logic with the actual Kidney Allocation Scheme, ii) to contrast it with another representation and reasoning mechanism applied in the USA based on Multiple Criteria Decision Making (MCDM) techniques, and iii) to develop a self-adaptive feedback model for adjustment of the decision makers' consistency of judgements when setting priorities. Despite the medical research carried out, this paper does not pretend to be an authority on medical decisions. The models can al...
ABSTRACT Tool magazine and automatic tool changer (ATC) are two of the most important key functio... more ABSTRACT Tool magazine and automatic tool changer (ATC) are two of the most important key functional units of the tool reserving and exchanging in machining center, reliability of which directly influences that of the machining centers. Failure analysis is the basic work in reliability analysis. So far, there is little in-depth and meticulous study about failure of the tool magazine and ATC, but there are many problems in the use of tool magazine and ATC. Based on the failure data received from field tracing tests, the failure modes, effects, and criticality analysis of the studied circular tool magazine and ATC are evaluated. The failure positions, causes, and criticalities in circular tool magazine and ATC, which have the highest criticality parameters are explored, offering the basis for the improvement in the design of the new products.
International Journal of Mechanical Engineering Education, 2011
ABSTRACT The paper reports on work carried out on an educational exercise for graduate and underg... more ABSTRACT The paper reports on work carried out on an educational exercise for graduate and undergraduate students that aids the study of Denavit-Hartenberg (DH) programming, through a real application within a ‘learning by doing’ scheme. The work presented to students requires the integration of the motion of an industrial robot (ASEA IRB 6) with a camera vision system (Baxall CD9752); they are asked to develop software that will support: the motion of the robot arm, including forward and reverse kinematics; the detection of an object on a test table; the picking up of the object; and its move to a target position on another test table. To assess the experiment, students select seven random points in the active camera area to determine the difference between the actual location of the end-effector and the location calculated using two methods: the trigonometric solutions and the DH parameters. Students discover that the trigonometric technique gives better position accuracy than DH. The project forms an excellent practical exercise to enhance student learning.
Integrated Reconfigurable Manufacturing Systems and Smart Value Chain, 2018
This chapter presents industrial revolutions and evolution of manufacturing systems (MSs) and inc... more This chapter presents industrial revolutions and evolution of manufacturing systems (MSs) and includes description of four industrial revolutions (IRs) and the literature survey on conventional MSs with the methodologies and tools used for system design and modelling. It presents definitions of MS concepts from a set of selective references and works, which have influenced on and led to development of the present RMS paradigm. To understand the evolution of MSs aimed at reconfigurability and the position of RMS among conventional MSs, the chapter commences by reviewing industrial revolutions and various types of production systems. Flexible manufacturing systems (FMSs), cellular manufacturing systems (CMSs), agile manufacturing systems (AMSs) and virtual cellular manufacturing systems (VCMS) are described with focusing on the concept, design and modelling aspects. In addition, the need to develop new methodologies aimed at greater flexibility through reconfigurability of MSs is presented.
The COVID-19 has placed pandemic modeling at the forefront of the whole world's public policymaki... more The COVID-19 has placed pandemic modeling at the forefront of the whole world's public policymaking. Nonetheless, forecasting and modeling the COVID-19 medical waste with a detoxification center of the COVID-19 medical wastes remains a challenge. This work presents a Fuzzy Inference System to forecast the COVID-19 medical wastes. Then, people are divided into five categories are divided according to the symptoms of the disease into healthy people, suspicious, suspected of mild COVID-19, and suspicious of intense COVID-19. In this regard, a new fuzzy sustainable model for COVID-19 medical waste supply chain network for location and allocation decisions considering waste management is developed for the first time. The main purpose of this paper is to minimize supply chain costs, the environmental impact of medical waste, and to establish detoxification centers and control the social responsibility centers in the COVID-19 outbreak. To show the performance of the suggested model, sensitivity analysis is performed on important parameters. A real case study in Iran/Tehran is suggested to validate the proposed model. Classifying people into different groups, considering sustainability in COVID 19 medical waste supply chain network and examining new artificial intelligence methods based on TS and GOA algorithms are among the contributions of this paper. Results show that the decision-makers should use an FIS to forecast COVID-19 medical waste and employ a detoxification center of the COVID-19 medical wastes to reduce outbreaks of this pandemic.
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Papers by Ashraf Labib