Bahareh Inanloo

Optimality versus stability in water resource allocation

Water allocation is a growing concern in a developing world where limited resources like fresh water are in greater demand by more parties. Negotiations over allocations often involve multiple groups with disparate social, economic, and political status and needs, who are seeking a management solution for a wide range of demands. Optimization techniques for identifying the Pareto-optimal (social planner solution) to multi-criteria multi-participant problems are commonly implemented, although often reaching agreement for this solution is difficult. In negotiations with multiple-decision makers, parties who base decisions on individual rationality may find the social planner solution to be unfair, thus creating a need to evaluate the willingness to cooperate and practicality of a cooperative allocation solution, i.e., the solutions stability. This paper suggests seeking solutions for multi-participant resource allocation problems through an economics-based power index allocation method. This method can inform on allocation schemes that quantify a partys willingness to participate in a negotiation rather than opt for no agreement. Through comparison of the suggested method with a range of distance-based multi-criteria decision making rules, namely, least squares, MAXIMIN, MINIMAX, and compromise programming, this paper shows that optimality and stability can produce different allocation solutions. The mismatch between the socially-optimal alternative and the most stable alternative can potentially result in parties leaving the negotiation as they may be too dissatisfied with their resource share. This finding has important policy implications as it justifies why stakeholders may not accept the socially optimal solution in practice, and underlies the necessity of considering stability where it may be more appropriate to give up an unstable Pareto-optimal solution for an inferior stable one. Authors suggest assessing the stability of an allocation solution as an additional component to an analysis that seeks to distribute water in a negotiated process.

Explosion impacts during transport of hazardous cargo: GIS-based characterization of overpressure impacts and delineation of flammable zones for ammonia

The aim of this research was to investigate accidental releases of ammonia followed by an en-route incident in an attempt to further predict the consequences of hazardous cargo accidents. The air dispersion model Areal Locations of Hazardous Atmospheres (ALOHA) was employed to track the probable outcomes of a hazardous material release of a tanker truck under different explosion scenarios. The significance of identification of the flammable zones was taken into consideration; in case the flammable vapor causes an explosion. The impacted areas and the severity of the probable destructions were evaluated for an explosion by considering the overpressure waves. ALOHA in conjunction with ArcGIS was used to delineate the flammable and overpressure impact zones for different scenarios. Based on the results, flammable fumes were formed in oval shapes having a chief axis along the wind direction at the time of release. The expansions of the impact areas under the overpressure value which can lead to property damage for 2 and 20 tons releases, under very stable and unstable atmospheric conditions were estimated to be around 1708, 1206; 3742, 3527 feet, respectively, toward the wind direction. A sensitivity analysis was done to assess the significance of wind speed on the impact zones. The insight provided by this study can be utilized by decision makers in transportation of hazardous materials as a guide for possible rerouting, rescheduling, or limiting the quantity of hazardous cargo to reduce the possible impacts after hazardous cargo accidents during transport.

Assessing the Stability of Social Planner Solutions in Multi-Participant Water Conflicts

The use of optimization techniques to identify socially optimal solutions to allocation problems is widely accepted in the water resources literature. For cases with multiple criteria and multiple decision makers (MC-MDM), techniques traditionally lump the decision makers (DM) into a single user and evaluate the criteria, thus not capturing the influence of power dynamics that occur between DMs. Through application of stability methods such as the power index, an alternative method for solving allocation problems, one can assess whether a decision rule is likely to be accepted based on the parties’ relative power. This work presents a method for applying the power index to MCMDM problems to determine the most stable decision rule. Since stability is concerned with minimizing the dissatisfaction of the most powerful party, stability can produce different outcomes from the conventional system-level optimization. This work presents this comparative analysis through a case study of the Caspian Sea resource allocation negotiation between five littoral states (Iran, Russia, Kazakhstan, Turkmenistan, and Azerbaijan). Goal programming, compromise programming, and power index methods are employed to evaluate the best scheme for allocation of the Caspian Sea resources. Results show that optimal solutions, analyzed by social planner methods, may not be stable in practice, as certain parties may be too dissatisfied with their allocation to enter into an agreement. This finding has important policy implications as it justifies why stakeholders may not accept the socially optimal solution in practice, and underlies the necessity of considering solution stability in social planning and decision making.