Jafar Rezaei | Jami - Academia.edu (original) (raw)
Papers by Jafar Rezaei
Maritime Economics & Logistics
Reliability of service times has long been a concern of many ports around the world. This paper p... more Reliability of service times has long been a concern of many ports around the world. This paper presents an approach to mitigate delays in service times through improved information sharing in ports. The approach is based on a mapping of information sharing links and their association to the root causes of frequently occurring delays. We identify the kind of information which is critical in mitigating delays. Critical information links are then re-ordered to create an information sharing arrangement between the actors, which further condenses and simplifies the required information sharing actions. We apply the proposed approach to the Port of Rotterdam. Quantitative data of 28,000 port calls is complemented by qualitative data collected through direct observations and expert interviews with port actors, including the pilot organization, a tugboat company, the boatmen organization, the harbour master, a terminal and a vessel agent. Besides the suggested arrangement for information s...
Journal of Behavioral Decision Making
International Journal of Logistics Research and Applications
This paper studies the factors that drive distribution structure design (DSD), which includes the... more This paper studies the factors that drive distribution structure design (DSD), which includes the spatial layout of distribution channels and location choice of logistics facilities. We build on a generic framework from existing literature, which we validate and elaborate using interviews among industry practitioners. Empirical evidence was collected from 18 logistics experts and 33 decision-makers affiliated to shippers and logistics service providers from the fashion, consumer electronics and online retail sectors. It turns out that interviewees share similar rankings of main factors across industries, and even confirm factor weights from earlier research established using multi-criteria decision analysis, which would indicate that the framework is sectorneutral at the highest level. The importance attached to subfactors varies between sectors according to our expectations. We were able to identify 20 possible new influencing subfactors. The results may support managers in their decision-making process, and regional policy-makers with regard to spatial planning and regional marketing. The framework is a basis for researchers to help improve further quantitative DSD support models.
IEEE Transactions on Engineering Management
Internet-of-Things (IoT) devices produce massive amounts of data, which are especially valuable w... more Internet-of-Things (IoT) devices produce massive amounts of data, which are especially valuable when shared between businesses. However, adoption of platforms that facilitate IoT data sharing is still low. Generic literature on interorganizational systems suggests a plethora of adoption factors, but typically focuses on data sharing between pairs of organizations. In a context of ecosystems, data governance becomes important, but its relative importance as an adoption factor is yet unclear. In this article, we examine the perception of IoT data providers regarding the relative importance of ecosystem data governance as an adoption factor, in comparison with generic adoption factors. Our study is situated in the horticulture domain, where data sharing potentially is highly valuable. We conduct a multicriteria decision-analysis survey using the best-worst method, complemented with interviews for interpreting findings. We find that businesses consider a large variety of factors equally important. Ecosystem data governance is in the middle-range, whereas factors like benefits and readiness are most important. At the same time, out of all adoption factors that platform providers can control directly, ecosystem data governance ranks among the highest. Our findings are important for informing data platform operators on what design issues to consider, in order to attract data owners. Index Terms-Information management. I. INTRODUCTION I NTERNET-OF-THINGS (IoT) devices in industry are generating large amounts of data on production processes [1]-[3]. Within businesses, IoT data enable monitoring and optimizing business processes, and even radically new business models [1], [3]-[5]. In practice, however, 90% of the data generated by IoT is not being used [6]. IoT data can become even more valuable when businesses share them with other businesses [7], [8]. However, when sharing large amounts of data within an ecosystem of many actors, ecosystem data governance becomes a crucial issue [26]-[28].
Journal of Cleaner Production
The concept of circular economy (CE), a recent popular global business trend, considerably minimi... more The concept of circular economy (CE), a recent popular global business trend, considerably minimizes waste and environmental pollution. However, studies exploring CE practices in the context of leather industry have been scant. To deal with this issue, this paper proposes a decision support framework for evaluating the challenges to CE practices in the context of leather industry. Best worst method, a generic decision support tool, is employed in the assessment process. The study findings reveal that "lack of financial support from authorities" is assigned the highest weight in the final ranking results. This indicates that the lack of financial facility poses a major challenge to the successful implementation of CE practices. The findings can assist industrial managers and authorities in taking the required actions to implement CE practices in the leather industry for the sustainable development of the leather sector.
Omega
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Transportation Research Part E: Logistics and Transportation Review
Hinterland freight transportation is managed according to a pre-designed schedule. In daily opera... more Hinterland freight transportation is managed according to a pre-designed schedule. In daily operations, unexpected uncertainties cause deviation from the original plan. Thus replanning is needed to deal with the perturbations and complete the transportation tasks. This paper proposes a mixed-integer programming model to re-plan hinterland freight transportation, based on the framework of synchromodality. It is a holistic resolution of shipment flow rerouting, consequence transshipment organization in the intermediate terminals, and corresponding service rescheduling. The replanning benefits from a high operational flexibility and coordination via a split of shipment and aligning the departure time of service flows with the shipment flows. 1. Introduction Hinterland freight transportation is carried out in accordance with an elaborated tactical plan. A service Network Design (SND) problem lies at the core of the tactical planning process, addressing issues like the selection and scheduling of services, specification of terminal operations and routing of shipment flows (Crainic, 2000). These plans are designed on the basis of predicted freight volume. Stochastic and robust planning are studied extensively to prevent or limit the influence of prediction bias. At the operational level, the tactical schedules are implemented on a local scale with a shorter time window. During this process, the transportation network is vulnerable to uncertainties and variations. Those not only rise from the external environment (unexpected additional or cancelled freight demands, weather caused hazards, delays of the shipment release), but can also internal from system fluctuations (congestion, breakdown and human-caused malpractices). The stochastic or robust planning plan is unable to handle all unexpected scenarios in everyday practice. It is still on open filed to regulate uncertainties at the operational level. Synchromodal transportation is an upcoming new solution succeeding intermodal transportation towards a more flexible and cooperated freight transportation (Tavasszy et al., 2010) at operational level to deal with uncertainties. Under the framework of synchromodality, shippers accept a mode-free booking and only determine the price and quality requirements (Behdani et al., 2016). The involved service providers collaborate under the centralized supervision of one Logistic Service Provider (LSP) (see also SteadieSeifi et al., 2014; Li et al., 2017 and Pérez and Mes, 2017). This implies that it is possible to perform real-time switching among different modes (Behdani et al., 2016). The centralized LSP holds the promise of generating specific replanning solutions to the specific uncertainties encountered in each individual case. The replanning questions come in: (1) Which part of the original SND plan can be re-planned? (2) To what degree can the re-planning solutions deviate from the SND plan? As mentioned above, the SND mainly consists of three components: the
Omega
The best-worst method (BWM) is a multi-criteria decision-making method which finds the optimal we... more The best-worst method (BWM) is a multi-criteria decision-making method which finds the optimal weights of a set of criteria based on the preferences of only one decision-maker (DM) (or evaluator). However, it cannot amalgamate the preferences of multiple decision-makers/evaluators in the so-called group decision-making problem. A typical way of aggregating the preferences of multiple DMs is to use the average operator, e.g., arithmetic or geometric mean. However, averages are sensitive to outliers and provide restricted information regarding the overall preferences of all DMs. In this paper, a Bayesian BWM is introduced to find the aggregated final weights of criteria for a group of DMs at once. To this end, the BWM framework is meaningfully viewed from a probabilistic angle, and a Bayesian hierarchical model is tailored to compute the weights in the presence of a group of DMs. We further introduce a new ranking scheme for decision criteria, called credal ranking , where a confidence level is assigned to measure the extent to which a group of DMs prefers one criterion over one another. A weighted directed graph visualizes the credal ranking based on which the interrelation of criteria and confidences are merely understood. The numerical example validates the results obtained by the Bayesian BWM while it yields much more information in comparison to that of the original BWM.
Journal of Cleaner Production
The concept of green supply chain management emerged as a response to increasing public awareness... more The concept of green supply chain management emerged as a response to increasing public awareness of environmental protection in the past few decades. As companies tend to outsource a variety of their activities, green supplier selection as an imperative function of green supply chain management, has a crucial role in helping companies to maintain their strategic competitiveness. Despite the plethora of studies introducing supplier selection models based on economic criteria, studies that take into account the environmental issues are rather limited. In this study, a comprehensive grey-based green supplier selection model is proposed that incorporates both economic and environmental criteria. A novel weight assignment model is proposed by combining best-worst method and fuzzy grey cognitive maps to capture the interdependencies among the criteria. Improved grey relational analysis is advanced to be able to use grey weights of criteria to evaluate green suppliers which are subsequently ranked using an interval analysis approach. This study contributes to the decision-making theory by addressing the shortcomings of the available green supplier selection models. A real-world case study is also presented to show the applicability and effectiveness of the proposed model. The results of this study proved the proposed comprehensive model to be well capable of addressing the green supplier selection problem by taking in to account the interdependencies between criteria as well as the uncertainties associated with experts' judgments.
Resources, Conservation and Recycling
A truly sustainable organization needs to take the economic, environmental and social dimensions ... more A truly sustainable organization needs to take the economic, environmental and social dimensions of sustainability into account. Although the economic and environmental dimensions of sustainability have been examined by many scholars and practitioners, thus far, the social dimension has been received less attention in literature and in practice, in particular in developing countries. Social sustainability enables other sustainability initiatives and overlooking this dimension can have a serious adverse impact across supply chains. To address this issue, this study proposes a framework for investigating the social sustainability of supply chains in manufacturing companies. To show the applicability and efficiency of the proposed framework, a sample of 38 experts was used to evaluate and prioritize social sustainability criteria, using a multi-criteria decision-making method called the 'best worst method' (BWM). The criteria are ranked according to their average weight obtained through BWM. The respondents view 'contractual stakeholders influence' as the most important social sustainability criterion. The results of this study help industry managers, decision-makers and practitioners decide where to focus their attention during the implementation stage, to increase social sustainability in their organizational supply chain and move towards sustainable development.
Scientific Journal of Kurdistan University of Medical Sciences, Apr 15, 2014
Journal of environmental management, Jan 24, 2016
Our current dependency on the oil and gas (O&G) industry for economic development and social acti... more Our current dependency on the oil and gas (O&G) industry for economic development and social activities necessitates research into the sustainability of the industry's supply chains. At present, studies on sustainable supply chain management (SSCM) practices in the industry do not include firm-internal factors that affect the sustainability strategies employed by different functional areas of its supply chains. Our study aims to address this gap by identifying the relevant internal factors and exploring their relationship with SSCM strategies. Specifically, we discuss the commitment to and preparedness for sustainable practices of companies that operate in upstream and downstream O&G supply chain. We study the impact of these factors on their sustainability strategies of four key supply chain functions: supplier management, production management, product stewardship and logistics management. The analyses of data collected through a survey among 81 companies show that management ...
Journal of Systems Science and Systems Engineering, 2014
ABSTRACT Automation systems for buildings interconnect components and technologies from the infor... more ABSTRACT Automation systems for buildings interconnect components and technologies from the information technology industry and the telecommunications industry. In these industries, existing platforms and new platforms (that are designed to make building automation systems work) compete for market acceptance and consequently several platform battles among suppliers for building automation networking are being waged. It is unclear what the outcome of these battles will be and also which factors are important in achieving platform dominance. Taking the fuzziness of decision makers’ judgments into account, a fuzzy multi-criteria decision-making methodology called the Fuzzy Analytic Hierarchy Process is applied to investigate the importance of such factors in platform battles for building automation networking. We present the relative importance of the factors for three types of platforms (subsystem platforms, system platforms, and evolved subsystem platforms). The results provide a first indication that the set of important factors differs per type of platform. For example, when focusing on other stakeholders, for subsystem platforms, the previous installed base is of importance; for system platforms, the diversity of the network of stakeholders is essential; and for evolved subsystem platforms, the judiciary is an important factor.
Supplier segmentation is a strategic business activity whereby suppliers of a firm are categorize... more Supplier segmentation is a strategic business activity whereby suppliers of a firm are categorized on the basis of their similarities. Instead of handling all suppliers separately, segmentation yields a manageable number of segments, each of which requires a similar strategy. Standard methods of supplier segmentation have serious shortcomings: they often use a limited number of criteria and do not capture the complicated interaction between different supplier aspects. There is often little by way of data that can be used to apply more advanced statistical segmentation approaches. In this paper, we use two overarching dimensions to capture all available segmentation criteria: supplier capabilities and supplier willingness. We propose two multi-criteria approaches to assess the position of suppliers with regard to these dimensions and subsequently that outcome to identify segments. These multi-criteria approaches, a fuzzy rule-based system and a DEA-like linear programming model are applied to a real-world case to demonstrate how the results can be used in practice. The results of the two approaches are compared and some strategies are suggested to handle different segments.
Complex optimization problems that cannot be solved using exhaustive search require efficient sea... more Complex optimization problems that cannot be solved using exhaustive search require efficient search metaheuristics to find optimal solutions. In practice, metaheuristics suffer from various types of search bias, the understanding of which is of crucial importance, as it directly pertinent to the problem of making the best possible selection of solvers. Two metrics are introduced in this study: one for measuring center-seeking bias (CSB) and one for initialization region bias (IRB). The former is based on "ξ-center offset", an alternative to "center offset", which is a common but, as will be shown, inadequate approach to analyzing the center-seeking behavior of algorithms. The latter is proposed on the grounds of "region scaling". The introduced metrics are used to evaluate the bias of three algorithms while running on a test bed of optimization problems having their optimal solution at, or near, the center of the search space. The most prominent finding of this paper is considerable CSB and IRB in the gravitational search algorithm (GSA). In addition, a partial solution to the center-seeking and initialization region bias of GSA is proposed by introducing a "mass-dispersed" version of GSA, mdGSA. The performance of mdGSA, which promotes the global search capability of GSA, is verified using the same mathematical optimization problem in addition to a gene regulatory network system parameter identification, the results of which demonstrate the capabilities of the mdGSA in solving real-world optimization problems.
Maritime Economics & Logistics
Reliability of service times has long been a concern of many ports around the world. This paper p... more Reliability of service times has long been a concern of many ports around the world. This paper presents an approach to mitigate delays in service times through improved information sharing in ports. The approach is based on a mapping of information sharing links and their association to the root causes of frequently occurring delays. We identify the kind of information which is critical in mitigating delays. Critical information links are then re-ordered to create an information sharing arrangement between the actors, which further condenses and simplifies the required information sharing actions. We apply the proposed approach to the Port of Rotterdam. Quantitative data of 28,000 port calls is complemented by qualitative data collected through direct observations and expert interviews with port actors, including the pilot organization, a tugboat company, the boatmen organization, the harbour master, a terminal and a vessel agent. Besides the suggested arrangement for information s...
Journal of Behavioral Decision Making
International Journal of Logistics Research and Applications
This paper studies the factors that drive distribution structure design (DSD), which includes the... more This paper studies the factors that drive distribution structure design (DSD), which includes the spatial layout of distribution channels and location choice of logistics facilities. We build on a generic framework from existing literature, which we validate and elaborate using interviews among industry practitioners. Empirical evidence was collected from 18 logistics experts and 33 decision-makers affiliated to shippers and logistics service providers from the fashion, consumer electronics and online retail sectors. It turns out that interviewees share similar rankings of main factors across industries, and even confirm factor weights from earlier research established using multi-criteria decision analysis, which would indicate that the framework is sectorneutral at the highest level. The importance attached to subfactors varies between sectors according to our expectations. We were able to identify 20 possible new influencing subfactors. The results may support managers in their decision-making process, and regional policy-makers with regard to spatial planning and regional marketing. The framework is a basis for researchers to help improve further quantitative DSD support models.
IEEE Transactions on Engineering Management
Internet-of-Things (IoT) devices produce massive amounts of data, which are especially valuable w... more Internet-of-Things (IoT) devices produce massive amounts of data, which are especially valuable when shared between businesses. However, adoption of platforms that facilitate IoT data sharing is still low. Generic literature on interorganizational systems suggests a plethora of adoption factors, but typically focuses on data sharing between pairs of organizations. In a context of ecosystems, data governance becomes important, but its relative importance as an adoption factor is yet unclear. In this article, we examine the perception of IoT data providers regarding the relative importance of ecosystem data governance as an adoption factor, in comparison with generic adoption factors. Our study is situated in the horticulture domain, where data sharing potentially is highly valuable. We conduct a multicriteria decision-analysis survey using the best-worst method, complemented with interviews for interpreting findings. We find that businesses consider a large variety of factors equally important. Ecosystem data governance is in the middle-range, whereas factors like benefits and readiness are most important. At the same time, out of all adoption factors that platform providers can control directly, ecosystem data governance ranks among the highest. Our findings are important for informing data platform operators on what design issues to consider, in order to attract data owners. Index Terms-Information management. I. INTRODUCTION I NTERNET-OF-THINGS (IoT) devices in industry are generating large amounts of data on production processes [1]-[3]. Within businesses, IoT data enable monitoring and optimizing business processes, and even radically new business models [1], [3]-[5]. In practice, however, 90% of the data generated by IoT is not being used [6]. IoT data can become even more valuable when businesses share them with other businesses [7], [8]. However, when sharing large amounts of data within an ecosystem of many actors, ecosystem data governance becomes a crucial issue [26]-[28].
Journal of Cleaner Production
The concept of circular economy (CE), a recent popular global business trend, considerably minimi... more The concept of circular economy (CE), a recent popular global business trend, considerably minimizes waste and environmental pollution. However, studies exploring CE practices in the context of leather industry have been scant. To deal with this issue, this paper proposes a decision support framework for evaluating the challenges to CE practices in the context of leather industry. Best worst method, a generic decision support tool, is employed in the assessment process. The study findings reveal that "lack of financial support from authorities" is assigned the highest weight in the final ranking results. This indicates that the lack of financial facility poses a major challenge to the successful implementation of CE practices. The findings can assist industrial managers and authorities in taking the required actions to implement CE practices in the leather industry for the sustainable development of the leather sector.
Omega
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Transportation Research Part E: Logistics and Transportation Review
Hinterland freight transportation is managed according to a pre-designed schedule. In daily opera... more Hinterland freight transportation is managed according to a pre-designed schedule. In daily operations, unexpected uncertainties cause deviation from the original plan. Thus replanning is needed to deal with the perturbations and complete the transportation tasks. This paper proposes a mixed-integer programming model to re-plan hinterland freight transportation, based on the framework of synchromodality. It is a holistic resolution of shipment flow rerouting, consequence transshipment organization in the intermediate terminals, and corresponding service rescheduling. The replanning benefits from a high operational flexibility and coordination via a split of shipment and aligning the departure time of service flows with the shipment flows. 1. Introduction Hinterland freight transportation is carried out in accordance with an elaborated tactical plan. A service Network Design (SND) problem lies at the core of the tactical planning process, addressing issues like the selection and scheduling of services, specification of terminal operations and routing of shipment flows (Crainic, 2000). These plans are designed on the basis of predicted freight volume. Stochastic and robust planning are studied extensively to prevent or limit the influence of prediction bias. At the operational level, the tactical schedules are implemented on a local scale with a shorter time window. During this process, the transportation network is vulnerable to uncertainties and variations. Those not only rise from the external environment (unexpected additional or cancelled freight demands, weather caused hazards, delays of the shipment release), but can also internal from system fluctuations (congestion, breakdown and human-caused malpractices). The stochastic or robust planning plan is unable to handle all unexpected scenarios in everyday practice. It is still on open filed to regulate uncertainties at the operational level. Synchromodal transportation is an upcoming new solution succeeding intermodal transportation towards a more flexible and cooperated freight transportation (Tavasszy et al., 2010) at operational level to deal with uncertainties. Under the framework of synchromodality, shippers accept a mode-free booking and only determine the price and quality requirements (Behdani et al., 2016). The involved service providers collaborate under the centralized supervision of one Logistic Service Provider (LSP) (see also SteadieSeifi et al., 2014; Li et al., 2017 and Pérez and Mes, 2017). This implies that it is possible to perform real-time switching among different modes (Behdani et al., 2016). The centralized LSP holds the promise of generating specific replanning solutions to the specific uncertainties encountered in each individual case. The replanning questions come in: (1) Which part of the original SND plan can be re-planned? (2) To what degree can the re-planning solutions deviate from the SND plan? As mentioned above, the SND mainly consists of three components: the
Omega
The best-worst method (BWM) is a multi-criteria decision-making method which finds the optimal we... more The best-worst method (BWM) is a multi-criteria decision-making method which finds the optimal weights of a set of criteria based on the preferences of only one decision-maker (DM) (or evaluator). However, it cannot amalgamate the preferences of multiple decision-makers/evaluators in the so-called group decision-making problem. A typical way of aggregating the preferences of multiple DMs is to use the average operator, e.g., arithmetic or geometric mean. However, averages are sensitive to outliers and provide restricted information regarding the overall preferences of all DMs. In this paper, a Bayesian BWM is introduced to find the aggregated final weights of criteria for a group of DMs at once. To this end, the BWM framework is meaningfully viewed from a probabilistic angle, and a Bayesian hierarchical model is tailored to compute the weights in the presence of a group of DMs. We further introduce a new ranking scheme for decision criteria, called credal ranking , where a confidence level is assigned to measure the extent to which a group of DMs prefers one criterion over one another. A weighted directed graph visualizes the credal ranking based on which the interrelation of criteria and confidences are merely understood. The numerical example validates the results obtained by the Bayesian BWM while it yields much more information in comparison to that of the original BWM.
Journal of Cleaner Production
The concept of green supply chain management emerged as a response to increasing public awareness... more The concept of green supply chain management emerged as a response to increasing public awareness of environmental protection in the past few decades. As companies tend to outsource a variety of their activities, green supplier selection as an imperative function of green supply chain management, has a crucial role in helping companies to maintain their strategic competitiveness. Despite the plethora of studies introducing supplier selection models based on economic criteria, studies that take into account the environmental issues are rather limited. In this study, a comprehensive grey-based green supplier selection model is proposed that incorporates both economic and environmental criteria. A novel weight assignment model is proposed by combining best-worst method and fuzzy grey cognitive maps to capture the interdependencies among the criteria. Improved grey relational analysis is advanced to be able to use grey weights of criteria to evaluate green suppliers which are subsequently ranked using an interval analysis approach. This study contributes to the decision-making theory by addressing the shortcomings of the available green supplier selection models. A real-world case study is also presented to show the applicability and effectiveness of the proposed model. The results of this study proved the proposed comprehensive model to be well capable of addressing the green supplier selection problem by taking in to account the interdependencies between criteria as well as the uncertainties associated with experts' judgments.
Resources, Conservation and Recycling
A truly sustainable organization needs to take the economic, environmental and social dimensions ... more A truly sustainable organization needs to take the economic, environmental and social dimensions of sustainability into account. Although the economic and environmental dimensions of sustainability have been examined by many scholars and practitioners, thus far, the social dimension has been received less attention in literature and in practice, in particular in developing countries. Social sustainability enables other sustainability initiatives and overlooking this dimension can have a serious adverse impact across supply chains. To address this issue, this study proposes a framework for investigating the social sustainability of supply chains in manufacturing companies. To show the applicability and efficiency of the proposed framework, a sample of 38 experts was used to evaluate and prioritize social sustainability criteria, using a multi-criteria decision-making method called the 'best worst method' (BWM). The criteria are ranked according to their average weight obtained through BWM. The respondents view 'contractual stakeholders influence' as the most important social sustainability criterion. The results of this study help industry managers, decision-makers and practitioners decide where to focus their attention during the implementation stage, to increase social sustainability in their organizational supply chain and move towards sustainable development.
Scientific Journal of Kurdistan University of Medical Sciences, Apr 15, 2014
Journal of environmental management, Jan 24, 2016
Our current dependency on the oil and gas (O&G) industry for economic development and social acti... more Our current dependency on the oil and gas (O&G) industry for economic development and social activities necessitates research into the sustainability of the industry's supply chains. At present, studies on sustainable supply chain management (SSCM) practices in the industry do not include firm-internal factors that affect the sustainability strategies employed by different functional areas of its supply chains. Our study aims to address this gap by identifying the relevant internal factors and exploring their relationship with SSCM strategies. Specifically, we discuss the commitment to and preparedness for sustainable practices of companies that operate in upstream and downstream O&G supply chain. We study the impact of these factors on their sustainability strategies of four key supply chain functions: supplier management, production management, product stewardship and logistics management. The analyses of data collected through a survey among 81 companies show that management ...
Journal of Systems Science and Systems Engineering, 2014
ABSTRACT Automation systems for buildings interconnect components and technologies from the infor... more ABSTRACT Automation systems for buildings interconnect components and technologies from the information technology industry and the telecommunications industry. In these industries, existing platforms and new platforms (that are designed to make building automation systems work) compete for market acceptance and consequently several platform battles among suppliers for building automation networking are being waged. It is unclear what the outcome of these battles will be and also which factors are important in achieving platform dominance. Taking the fuzziness of decision makers’ judgments into account, a fuzzy multi-criteria decision-making methodology called the Fuzzy Analytic Hierarchy Process is applied to investigate the importance of such factors in platform battles for building automation networking. We present the relative importance of the factors for three types of platforms (subsystem platforms, system platforms, and evolved subsystem platforms). The results provide a first indication that the set of important factors differs per type of platform. For example, when focusing on other stakeholders, for subsystem platforms, the previous installed base is of importance; for system platforms, the diversity of the network of stakeholders is essential; and for evolved subsystem platforms, the judiciary is an important factor.
Supplier segmentation is a strategic business activity whereby suppliers of a firm are categorize... more Supplier segmentation is a strategic business activity whereby suppliers of a firm are categorized on the basis of their similarities. Instead of handling all suppliers separately, segmentation yields a manageable number of segments, each of which requires a similar strategy. Standard methods of supplier segmentation have serious shortcomings: they often use a limited number of criteria and do not capture the complicated interaction between different supplier aspects. There is often little by way of data that can be used to apply more advanced statistical segmentation approaches. In this paper, we use two overarching dimensions to capture all available segmentation criteria: supplier capabilities and supplier willingness. We propose two multi-criteria approaches to assess the position of suppliers with regard to these dimensions and subsequently that outcome to identify segments. These multi-criteria approaches, a fuzzy rule-based system and a DEA-like linear programming model are applied to a real-world case to demonstrate how the results can be used in practice. The results of the two approaches are compared and some strategies are suggested to handle different segments.
Complex optimization problems that cannot be solved using exhaustive search require efficient sea... more Complex optimization problems that cannot be solved using exhaustive search require efficient search metaheuristics to find optimal solutions. In practice, metaheuristics suffer from various types of search bias, the understanding of which is of crucial importance, as it directly pertinent to the problem of making the best possible selection of solvers. Two metrics are introduced in this study: one for measuring center-seeking bias (CSB) and one for initialization region bias (IRB). The former is based on "ξ-center offset", an alternative to "center offset", which is a common but, as will be shown, inadequate approach to analyzing the center-seeking behavior of algorithms. The latter is proposed on the grounds of "region scaling". The introduced metrics are used to evaluate the bias of three algorithms while running on a test bed of optimization problems having their optimal solution at, or near, the center of the search space. The most prominent finding of this paper is considerable CSB and IRB in the gravitational search algorithm (GSA). In addition, a partial solution to the center-seeking and initialization region bias of GSA is proposed by introducing a "mass-dispersed" version of GSA, mdGSA. The performance of mdGSA, which promotes the global search capability of GSA, is verified using the same mathematical optimization problem in addition to a gene regulatory network system parameter identification, the results of which demonstrate the capabilities of the mdGSA in solving real-world optimization problems.