Erkan Celik

A comprehensive review of multi criteria decision making approaches based on interval type-2 fuzzy sets

A literature review of IT2FSs based MCDM approaches is presented.The systematic classification covers 35 MCDM approaches as single and hybrid.It provides an insight for researchers on IT2FSs based MCDM approaches. Multi criteria decision making (MCDM) is a discipline of operations research which has widely studied by researchers and practitioners. It deals with evaluating and ranking alternatives from the best to the worst under conflicting criteria with respect to decision maker(s) preferences. Since, many real-world systems include uncertainty and vagueness in information, MCDM uses fuzzy sets. In recent years, as an extension of the traditional fuzzy sets concept, type-2 fuzzy sets are preferred to have the capability of handling more uncertainty, and hence, to produce more accurate and robust results, MCDM approaches based on interval type-2 fuzzy sets (IT2FSs) have been published in various subjects. This paper reviews 82 different papers using various MCDM approaches based on IT2FSs which are classified into 35 categories. All papers with respect to single and hybrid approaches are discussed, pointing out their real applications or empirical results and limitations. Furthermore, the papers are statistically analyzed to show new trends within the context of IT2FSs. This systematic and comprehensive review study provides an insight for researchers on interval type-2 fuzzy MCDM in terms of showing current state and potential areas to be focused in the future.

A trapezoidal type-2 fuzzy MCDM method to identify and evaluate critical success factors for humanitarian relief logistics management

Disaster and humanitarian logistics are one of the most important subjects for a country to take care about. It is possible to increase the performance of humanitarian relief logistics management processes by several planning and prevention activities. This papers main contribution is identifying and then evaluating the success factors which are critical for effective management of humanitarian relief logistics operations. Therefore, an effective method that combines type-2 fuzzy sets, which provide additional degrees of freedom to present the uncertainty and the fuzziness of the real world, and analytic hierarchy process, is proposed to sustain a realistic evaluation. It is aimed that, the proposed method will be used by governmental and non-governmental organizations to improve their HRLM activities and strategies.

An assessment approach for non-governmental organizations in humanitarian relief logistics and an application in Turkey

Abstract.The ever-increasing natural disasters have been causing the loss of lives, properties and resources. By the preparedness and response ability of non-governmental organizations, it is aimed to minimize these losses. In this paper, first, the critical success factors of humanitarian relief logistics management operations are determined and categorized. Then, by considering these factors, a hybrid method that consists of trapezoidal interval type-2 fuzzy sets, AHP and TOPSIS, is proposed to evaluate emergency preparedness and response ability performance of non-governmental relief organizations. The proposed hybrid method is applied for non-governmental relief organizations in Turkey to evaluate their performance, and to the factors need to be improved for each determined organization.

A hybrid risk-based approach for maritime applications: The case of ballast tank maintenance

ABSTRACT Risk assessment is vital for cost-effective ship management in maritime industry since numerous maritime activities pose potential hazards according to the human causalities. Therefore, safety practitioners attempt to offer proactive approaches to mitigate risk as much as possible. In this context, this article presents a hybrid risk-based approach for maritime industry by adopting Fuzzy Analytic Hierarchy Process (FAHP) with fuzzy VIKOR (FVIKOR) methods under Fine-Kinney approach. To illustrate the hybrid risk-based approach, ballast tank maintenance process is handled since there are various hazards causing fatalities, severe injuries, and illness during ballast tank maintenance procedure than any other type of shipboard work. An extensive risk analysis is performed to enhance environment safety and operational reliability in maritime industry. Besides its theoretical contribution, the outcomes of the paper contribute to improve overall safety level of ship by considering potential hazards in risk management.

A New Extension of the ELECTRE Method Based Upon Interval Type-2 Fuzzy Sets for Green Logistic Service Providers Evaluation

Increase in environmental pollution makes companies give more importance to this issue, and as such, there is a need to take into account the necessary precautions. In particular, logistics service providers who are interwoven with the environment should apply some policies to increase environmental awareness. In this paper, we extended the ELECTRE method and proposed a new methodology for handling fuzzy multi criteria decision making problems based upon interval type-2 fuzzy sets. Interval type-2 fuzzy sets provided more df to reflect the uncertainty and the fuzziness of the real applications. An empirical study was presented in order to evaluate the green logistics service providers. A sensitivity analysis was applied to discuss and evaluate the greenness of the logistic service providers.

Emergency department performance evaluation by an integrated simulation and interval type-2 fuzzy MCDM-based scenario analysis

Emergency departments (EDs) have an important position in healthcare system environment because of their serviceability to the patients with several illnesses and injuries at all hours of the day and night. Therefore, efficient management of these departments by executives and service providers is only possible with effective tools such as simulation. The concept of multiple criteria decision-making (MCDM) is applicable by computer simulation for decision analysis and performance evaluation of an ED. This study proposes an integration of computer simulation, MCDM methods of interval type-2 fuzzy analytic hierarchy process (IT2FAHP), and ELECTRE for an ED system in a university hospital. Due to the high uncertainty in ED operations, interval type-2 fuzzy sets (IT2FSs) are used in MCDM process. Consequently, the integrated method can be used as a useful tool to evaluate the ED performance and select the best scenario considering different numbers of nurses and doctors for three shifts. [Received 30 July 2013; Revised 9 February 2015; Accepted 14 June 2015]

A new approach for rebalancing of U-lines with stochastic task times using ant colony optimisation algorithm

In real world, line balancing involves existing lines in existing factories and the line typically needs to be rebalanced rather than balanced. Rebalancing of a U-line can be defined as a changeover process from its initial configuration to a new configuration for a while due to the reasons such as demand variations, changes in product design and changes in task times, etc. This study defines U-line rebalancing problem with stochastic task times and proposes a solution procedure based on ant colony optimisation. The objective of the proposed algorithm is to minimise total cost of rebalancing which is the sum of task transposition costs, workstation opening/closing costs and operating costs of workstations for a particular planning horizon. A comprehensive experiment is conducted to generate problem instances and to compare rebalancing costs of U-lines by means of several factors. A total of 6600 rebalancing solutions are obtained and several comparisons are performed.

Assessment of occupational hazards and associated risks in fuzzy environment: A case study of a university chemical laboratory

ABSTRACT University laboratories involve various occupational hazards during the research and course activities, which might affect health and safety of both researchers and students, including chemical, physical, electrical, mechanical, as well as ergonomic and psychosocial risk factors. There are many aspects open to improvements in Occupational Health and Safety management of laboratories, and it is required to deal with risks, reduce them in an acceptable level, and implement control measures. In this study, a risk assessment approach is proposed for the university laboratory operations. The proposed approach incorporates 5S methodology, failure modes and effects analysis (FMEA), interval type-two fuzzy sets (IT2FSs), analytic hierarchy process (AHP), and the VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR). AHP is injected into IT2FSs in the phase of evaluation and weighting of severity (S), occurrence (O), and detectability (D) parameters of FMEA. By applying IT2FVIKOR, it is aimed at prioritizing the emerged hazards in the chemical laboratory of the observed university. The proposed approach reveals the important hazards and suggests control measures for managing them. The study methodologically contributes to risk assessment in the knowledge, while a case study in a chemical laboratory of a newly established university offers an insight into education industry in safety improvement.

A practical application of human reliability assessment for operating procedures of the emergency fire pump at ship

ABSTRACT This paper aims to conduct a practical application for human reliability assessment during operating procedures of an emergency fire pump on-board ship. A systematic human error prediction is performed for designated tasks during operational procedures of the emergency fire pump since human error can be regarded as one of the major factors contributing accidents at sea. Hence, human reliability performance is evaluated to enhance fire safety management in operational level on-board ship. In the paper, marine-specific error producing conditions are adopted under fuzzy sets environment. To enhance consistency of research and minimise subjectivity during experts judgement stage, the paper is supported with a dominance factor which is used to adjust the impact level of experts judgments in the aggregation stage of the methodology. The outcomes of the paper provide valuable contributions to the safety managers and technical superintends to monitor fire safety management and crew reliability performance.

Fuzzy rule-based Fine–Kinney risk assessment approach for rail transportation systems

ABSTRACT Rail transportation is one of the most crucial public transportation types for big and crowded cities. In rail transportation systems, stakeholders face serious issues involved in workshops, stations, lines and their environments, and general office buildings. In order to reach an increased awareness and better occupational health and safety (OHS) management, a new risk assessment approach is proposed in this study. This approach includes a combination of Fine–Kinney method and a fuzzy rule-based expert system. It captures nonlinear causal relationships between Fine–Kinney parameters. Since there is a high level of vagueness involved in the OHS risk assessment data, the rule-based expert system is developed for probability (P), exposure (E), and consequence (C) for evaluating risk score. A case study is carried out in a rail transportation system in Istanbul/Turkey, and a comparison with the classical Fine–Kinney method is discussed. Results of the case study reveal risk clusters and corresponding control measures that should be taken into consideration. The study methodologically contributes to risk assessment in the knowledge, while case study in a real rail transportation system offers an insight into public transport industry in safety improvement.