Three-level trade-off analysis for decision making in environmental engineering under interval uncertainty

A three-level trade-off analysis is proposed for decision making in environmental engineering under interval uncertainty, capable of providing both extreme and non-extreme decision alternatives at different risk levels for constraint and objective function violations. The essence of three-level trade-off analysis is the use of both modified interval linear programming and enhanced interval linear programming models to generate risk-based decision alternatives by qualitatively dividing the risk levels of the parameters in both the constraints and the objective function. The generated decision alternatives include two extremes, two appropriate values and one expected value, and two other non-extremes. The results of a numerical example and a real-world case study (Lake Qionghai Watershed, China) indicate that this procedure can support decision-making processes for stakeholders at different levels of risk to system benefits, within absolutely feasible and optimal solution spaces.