An aggregated fuzzy model for the selection of a managed security service provider

In this study, by analyzing the related literature, the companies providing security services and, more importantly, the data provided by a group of experts, a novel set of 39 criteria is extracted which assists the Managed Security Service Provider (MSSP) selection process. The set is further categorized into eight general classes. The validity and weights of these criteria are measured by a group of experts in Iran. Due to the large number and often conflicting criteria, and the qualitative nature of the evaluations of the service providers, fuzzy multi-criteria decision-making methods (FMCDM) are adopted. In order to demonstrate the application of the proposed model, a numerical example is included, in which eight service providers are evaluated by four decision makers applying fuzzy TOPSIS, fuzzy VIKOR, fuzzy Group ELECTRE, and fuzzy SAW methods. Owing to the variations of the outputs of the applied MCDM methods, they are further analyzed by an aggregation method to propose a unique service provider. A comparison between the output of the aggregation method and the four applied Fuzzy MCDM methods is also made with the help of Euclidean, Hamming, Manhattan and Chebyshev distances. The comparison shows the minimum diversion between the outputs of the Fuzzy TOPSIS and the aggregation method, which indicates the appropriateness of the fuzzy TOPSIS method in this particular problem

Hybrid meta-heuristic algorithms for a supply chain network considering different carbon emission regulations using big data characteristics

Big data (BD) approach has significantly impacted on the development and expansion of supply chain network management and design. The available problems in the supply chain network (SCN) include production, distribution, transportation, ordering, and inventory holding problems. These problems under the BD environment are challenging and considerably affect the efficiency of the SCN. The drastic environmental and regulatory changes around the world and the rising concerns about carbon emissions have increased the awareness of customers regarding the carbon footprint of the products they are consuming. This has enforced supply chain managers to change strategies to reframe carbon emissions. The decisions such as an optimization of the suitable network of the proper lot sizes can play a crucial role in minimizing the whole carbon emissions in the SCN. In this paper, a new integrated production–transportation–ordering–inventory holding problem for SCN is developed. In this regard, a mixed-integer nonlinear programming (MINLP) model in the multi-product, multi-level, and multi-period SCN is formulated based on the minimization of the total costs and the related cost of carbon emissions. The research also uses a chance-constrained programming approach. The proposed model needs a range of real-time parameters from capacities, carbon caps, and costs. These parameters along with the various sizes of BD, namely velocity, variety, and volume, have been illustrated. A lot-sizing policy along with carbon emissions is also provided in the proposed model. One of the important contributions of this paper is the three various carbon regulation policies that include carbon capacity-and-trade, the strict capacity on emission, and the carbon tax on emissions in order to assess the carbon emissions. As there is no benchmark available in the literature, this study contributes toward this aspect by proposing two hybrid novel meta-heuristics (H-1) and (H-2) to optimize the large-scale problems with the complex structure containing BD. Hence, a generated random dataset possessing the necessary parameters of BD, namely velocity, variety, and volume, is provided to validate and solve the suggested model. The parameters of the proposed algorithms are calibrated and controlled using the Taguchi approach. In order to evaluate hybrid algorithms and find optimal solutions, the study uses 15 randomly generated data examples having necessary features of BD and T test significance. Finally, the effectiveness and performance of the presented model are analyzed by a set of sensitivity analyses. The outcome of our study shows that H-2 is of higher efficiency