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Construction projects are associated with a number of uncertainties due to their expanse, complex nature, uniqueness, and dynamic states. Risks in construction projects are, indeed, the events or uncertain situations that can have negative or positive consequences on the project objectives. Many of the risks inherent in construction projects affect each other. For example, the time risk in construction projects can affect the cost risk and vice versa. The intertwined relations between risk factors are ignored in the traditional construction risk assessment methods. To fulfill this gap, this paper proposes an integrated fuzzy DEMATEL-fuzzy ANP model to evaluate construction projects and their overall risks by considering intertwined relations among risk factors. Fuzzy DEMATEL is used to determine the interrelationships and interdependencies among risk factors. The network structure for implementing the fuzzy ANP method is extracted based on the results of fuzzy DEMATEL. The fuzzy ANP is applied to assess the relative importance of risk factors and alternatives and prioritize construction projects. The proposed integrated model is used to evaluate five construction projects based on risk factors in Isfahan, Iran. The results of applying the integrated model reveal that the time, cost and safety risks with the weight values of 0.056, 0.038, and 0.034 are the most important factors among construction risks, respectively. The results reveal that the proposed model can help managers to evaluate the overall risks of construction projects, and select the best project that has the lowest risk.

Most of current logistics network design models in the literature typically assume that facilities are always available and absolutely reliable while in practice, they are always subject to several operational and disruption risks. This paper proposes a reliable closed-loop supply chain network design model, which accounts for both partial and complete facility disruptions as well as the uncertainty in the critical input data. The proposed model is of mixed integer possibilistic linear programming type that aims to minimise simultaneously the total cost of opening new facilities and the expected cost of disruption scenarios. An enhanced possibilistic programming approach is proposed to deal with the epistemic uncertainty in input data. Furthermore, the p-robustness criterion is used to limit the cost of disruption scenarios and protect the designed network against random facility disruptions. Several numerical experiments along with sensitivity analyses on uncertain parameters are conducted to illustrate the significance and applicability of the developed model as well as the effectiveness of the proposed solution approach. Our results demonstrate that operational and disruption risks considerably affect the whole structure of the designed network and they must be taken into account when designing a reliable closed-loop logistics network.

Due to the increasing population and earth pollution, managing construction and infrastructure projects with less damage to the environment and less pollution is very important. Sustainable development aims at reducing damage to the environment, making projects economical, and increasing comfort and social justice. This study proposes fuzzy analytic hierarchy process (AHP) and improved grey relational analysis (GRA) to assess construction projects based on the sustainable development criteria. For doing so, sustainable development criteria are first identified in economic, social, and environmental dimensions using literature review, and are then customized for urban construction projects using experts' opinions. After designing questionnaires and collecting data, fuzzy AHP is used for determining the importance of sustainable development criteria and their subcriteria. Then, improved GRA is employed for assessing six recreational, commercial, and official centers in Isfahan regarding the weights of criteria and subcriteria. The proposed fuzzy AHP-improved GRA help us to prioritize construction projects based on the sustainable development criteria. The results of applying fuzzy AHP show that the weights of economic, social, and environmental criteria are equal to 0.330, 0.321, and 0.349, respectively, which are close to each other. This means that the importance of all three aspects of sustainability is almost equal to each other. Furthermore, "Having profits for the society", "Increasing social justice", and "Adherence to environmental policies" are identified as the most important indicators of sustainable development in terms of economic, social, and environmental aspects, respectively. Finally, the results of employing improved GRA determine Negin Chaharbagh recreational and commercial complex as the best project.