Solid waste management under uncertainty: a generalized fuzzy linear programming approach

In this study, a generalized fuzzy linear programming (GFLP) method is developed to identify optimal waste-flow-allocation schemes under uncertainty. A stepwise interactive algorithm (SIA) is advanced to solve the GFLP model and generate solutions expressed as fuzzy sets. This solution method can handle fuzzy sets with known membership functions, regardless of the shapes of these functions. Moreover, solutions expressed as fuzzy sets can also be obtained through SIA. The developed method is applied to a case study of waste allocation planning problem under uncertainty. The results indicate that reasonable solutions can be obtained for planning waste allocation practices. Compared with interval solutions derived from interval linear programming method, the fuzzy solutions obtained through GFLP can provide more information. Therefore, the decision-makers can make tradeoffs between system stability and plausibility and thus identify desired policies for solid waste planning under uncertainty.