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Double row facility layout problem (DRFLP) is a frequently used layout type in flexible manufacturing systems. In this layout, machines or departments are placed along both sides of a corridor, which is a path for the use of transportation vehicles and workers. The problem involves determining which side of the corridor the machines will be on and their exact locations on the row in order to minimize transportation costs within the facility. This study focuses on a multi-product DRFLP with different processing routes. New mixed integer mathematical models were developed for the scenarios with and without identical machines. The effectiveness of the models was evaluated on the randomly generated test problems. Optimal solutions were obtained in both models for small-sized problems. For large-sized problems, the solution values reached within pre-determined time limit (21600 s) were reported. While the gap (%) values at the end of the solution time determined in the model without identical machines ranged between 8.05 and 32.26, these values were between 5.26 and 25.73 for the model with identical machines. [ABSTRACT FROM AUTHOR]

Single row facility layout problem is the problem of arranging departments on a straight line. The main objective of the single row facility layout problem is to minimize the total material handling cost. However, it is not explanatory to use one objective. Hence, researchers pay more attention to model facility layout problems with qualitative and quantitative objectives. In this study, a weighted goal programming approach and a NSGA-II algorithm are proposed to solve multi-objective single row facility layout problem with the objectives of minimizing total flow distance and maximizing closeness rating scores. These objectives are taken into account for single row facility layout problem, for the first time, in this paper. [ABSTRACT FROM AUTHOR]

In this study, a new failure mode and effects analysis (FMEA) model is proposed for evaluating occupational safety risks. In the classical FMEA, risk priority numbers (RPNs) are calculated by multiplying the risk scores of the occurrence, severity, and detectability. However, RPN numbers generated by classical FMEA have been the subject of severe criticism in the literature. To overcome the drawbacks of the classical FMEA, this study proposes a new Multiple Attribute Decision Making (MADM) model. The proposed risk evaluation model combines the full consistency method (FUCOM) and graph theorymatrix approach (GTMA) under a fuzzy environment. The risk scores of failure models and the weights of risk factors have been obtained using the fuzzy FUCOM method. On the other hand, the RPN value of each failure mode is calculated by utilizing fuzzy GTMA. Fuzzy GTMA considers all possible dependencies among risk factors, which in turn produces more accurate rankings. The fuzzy judgements of the decision makers are aggregated by using the least squares distance method. The proposed model is implemented in a real-life case study and the failure modes are ranked. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new hybrid meta-heuristic algorithm based on simulated annealing supplemented with tabu list for the Multi Objective Facility Layout Problem (MOFLP). It is a SA approach supplemented with a tabu list. The main advantage of this approach is that a short term memory provided by the tabu list can be used to avoid solution re-visits while preserving the stochastic nature of the SA method. The goal of the new hybrid heuristic algorithm is to find the solutions forming the set of efficient solutions (pareto optimal set) of the MOFLP's in a relatively short time. The hybrid meta-heuristic is illustrated with a practical example of plant with 8 departments and 4 objectives. An efficient set of layouts corresponding to pre-determined weights are obtained. And also the set of efficient pareto-optimal solutions of the problem are determined. [ABSTRACT FROM AUTHOR]

In today's market conditions, increasing global competition, rapid changes in technology and shorter life cycle of product the facility layout to be evaluated as the dynamic facility layout problem (DFLP). The purpose of DFLP is to assign the departments to locations for a multi-period planning horizon so that the sum of the material handling and rearrangement costs is minimized. DFLP is generally formulated as a quadratic assignment problem (QAP) which is NP-hard. The larger the size of the problem, the harder to find the optimal solution. In this paper, a simulated annealing (SA) heuristic is developed to solve the DFLP. To test the performance of the proposed SA heuristic, a set of problems from literature is used. The results obtained show that the proposed heuristic is very effective for DFLP. [ABSTRACT FROM AUTHOR]