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An enhanced radial interval programming approach was developed for supporting the identification of sound agricultural production plans. It was designed to tackle dual uncertainties in both the economic and environmental subsystems as well as reflect differential aspiration levels for 'immunity' against such uncertainty. By adding protection functions to both the objective functions and constraints susceptible to dual uncertainties without any distributions, it improved upon previous methods through simultaneously measuring and manipulating expected return risk and resource-environmental compliance risk. Moreover, this study made novel attempts to explore system-wide optimal levels of robustness based on proposed performance evaluation criteria and investigations over the interactive effects of varied robustness aspirations for different model components. Based on analyzed tradeoffs among system optimality, robustness and uncertainty degree of solutions pertaining to the study case, a unified protection level of 13 (or 10) was recommended for risk-averse (or risk-neutral) decision making. The model outputs were compared to those from three alternatives, revealing that it could achieve a high level of system reliability at a minor price of economic return. This approach could be generalized for wide-scale applications. [ABSTRACT FROM AUTHOR]

In this research, an export coefficient based dual inexact two-stage stochastic credibility constrained programming (ECDITSCCP) model was developed through integrating an improved export coefficient model (ECM), interval linear programming (ILP), fuzzy credibility constrained programming (FCCP) and a fuzzy expected value equation within a general two stage programming (TSP) framework. The proposed ECDITSCCP model can effectively address multiple uncertainties expressed as random variables, fuzzy numbers, pure and dual intervals. Also, the model can provide a direct linkage between pre-regulated management policies and the associated economic implications. Moreover, the solutions under multiple credibility levels can be obtained for providing potential decision alternatives for decision makers. The proposed model was then applied to identify optimal land use structures for agricultural NPS pollution mitigation in a representative upstream subcatchment of the Miyun Reservoir watershed in north China. Optimal solutions of the model were successfully obtained, indicating desired land use patterns and nutrient discharge schemes to get a maximum agricultural system benefits under a limited discharge permit. Also, numerous results under multiple credibility levels could provide policy makers with several options, which could help get an appropriate balance between system benefits and pollution mitigation. The developed ECDITSCCP model can be effectively applied to addressing the uncertain information in agricultural systems and shows great applicability to the land use adjustment for agricultural NPS pollution mitigation. [ABSTRACT FROM AUTHOR]

In this research, an interval-parameter two-stage stochastic programming approach was developed for supporting the identification of low-carbon strategies and the post-earthquake reconstruction in the city of Gugangyuan, Sichuan province of China. The approach can effectively deal with uncertainties that can be expressed as both probability density functions and interval numbers without any distribution information. Also, the approach can provide useful decision alternatives for supporting long-term corrections for any plans associated with carbon dioxide emission limits within a city context. The developed approach was applied in the city of Guangyuan. Three scenarios were established including the baseline (i.e., regional planning) as scenario 1, zero carbon emission as scenario 2, and carbon sink as scenario 3. Also, based on practical information and the collected data, three projection values (i.e., low, medium and high levels) for the carbon emission of the entire city were generated and analyzed under varying probability levels (i.e., 20, 60, and 20%). The results indicated that in order to achieve low-carbon post-earthquake development in the city, the priority areas and industries for carbon emission reduction would be Chaotian (the secondary industry) > Wangcang (the secondary industry) > Lizhou (the secondary industry) = Qingchuan (the tertiary industry) > Cangxi (the secondary industry) = Chaotian (the tertiary industry). [ABSTRACT FROM AUTHOR]