Muhammet Gul

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 comprehensive review of emergency department simulation applications for normal and disaster conditions

A literature review of ED simulations for normal and disaster conditions is presented.The systematic classification covers 106 reviewed papers.It provides an insight for researchers on ED simulation modelling. Hospital emergency departments (HEDs) are the most critical units since they undertake a vital health care mission. It is required for these departments to find out rational solution methods in case of issues occurred in normal and disaster times. Simulation is an effective method to improve policies on operational, tactical and strategic decisions about EDs. The main reasons prompting us to do this study are to reveal the importance of simulation for disaster preparedness of EDs and the innovative aspects of recent ED simulation applications unlike the available literature surveys. This systematic and comprehensive review study can provide an insight for researchers on ED simulation modeling in terms of showing current state and gaps to be focused in the future.

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.

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]

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 review of occupational health and safety risk assessment approaches based on multi-criteria decision-making methods and their fuzzy versions

ABSTRACT Occupational health and safety (OHS) is a multidisciplinary activity working under the tasks of protection of workers and worksites. Risk assessment, as a compulsory process in implementation of OHS, stands out as evaluating the risks arising from the hazards, taking into account the required control measures, and deciding whether or not the risks can be reduced to an acceptable level. The diversity in risk assessment approaches is such that there are many methods for any industry. Multicriteria decision-making (MCDM)-based approaches contribute to risk assessment knowledge with their ability on solving real-world problems with multiple, conflicting, and incommensurate criteria. This article conducts a critical state-of-the-art review of OHS risk assessment studies using MCDM-based approaches. Additionally, it includes fuzzy versions of MCDM approaches applied to OHS risk assessment. A total of 80 papers are classified in eight different application areas. The papers are reviewed by the points of publication trend, published journal, risk parameters/factors, and tools used. This critical review provides an insight for researchers and practitioners on MCDM-based OHS risk assessment approaches in terms of showing current state and potential areas for attempts to be focused in the future.

Are Emergency Departments in Istanbul Ready for the Earthquakes? Past Experience and Suggestions for Future Preparedness from Employees’ Viewpoint and the Literature

Abstract This paper aims to review what is known about the preparedness of hospital emergency departments (EDs) for a possible major earthquake expected in the near future in Istanbul and reveal the past experience and future plans from employees’ viewpoints and, as well as from the related literature. For this purpose, potential effects of the earthquakes on ED operations, patient flow, and performance are discussed considering the statistical data of recent earthquakes in Turkey, a comprehensive report on the disaster preparedness of Istanbul and, one to one interviews with the earthquake experienced ED medical staff. In particular, issues on patient surge, triage and registration, communication, patient flow and transportation and, lack of enough resources and space to treat are presented as the main challenges. According to the viewpoints obtained from various sources, EDs in Istanbul are not ready to meet the needs caused by a major earthquake. It is proposed that operational research (OR) techniques can be useful to overcome these issues such as simulation modeling.

A discrete event simulation model of an emergency department network for earthquake conditions

Emergency departments (EDs) are the first admission points of hospitals for patients (victims) during normal and disaster conditions. To meet the uncertain patient demand, make the first examination, discharge or admit into impatient units are included in responsibility of these departments. Resource design of emergency departments in order to struggle patient surge for earthquake disaster conditions affects ED performance measures such as patient length of stay (LOS), human and treatment area utilization and queue length. In this study, an ED network consisting of five public hospital emergency departments where located in the earthquake zone of Istanbul is modeled by discrete event simulation (DES). The aim of the study is to (1) model the ED network for normal conditions, (2) generate earthquake related scenarios, and (3) develop a health care decision and policy making tool for stakeholders.

Evaluating occupational health and safety service quality by SERVQUAL: a field survey study

The adverse impact of occupational accidents and occupational diseases on the society have recently increased a lot since the industrial-oriented society is getting more and more widespread. Although attempts regarding occupational health and safety (OHS) increase in Turkey, they are still at an inadequate level. OHS experts prepare employees for a healthy and safer working environment, so that work accidents can be eliminated and employees can be healthy psychologically and physically. At the same time, the worksites can be prevented from being financially damaged and productivity can be improved. The aim of this study is to measure OHS service quality by the evaluations of OHS experts from various sectors and workplaces. In this way, the OHS performance is measured, the difference between perceptions and expectations of the OHS experts is determined and deficiencies are revealed. In the study, the OHS activities are examined in five dimensions using the SERVQUAL scale; tangibility, reliability, responsiveness, assurance and empathy. The questionnaire is carried out using a Likert-type five-point scale among 81 OHS experts from different sectors. In conclusion, SERVQUAL analysis is introduced as a useful tool for employers to better understand what they need to know about OHS services.

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.