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In this paper, a coordinated-distributed model predictive control (CDMPC) scheme is presented for discrete-time linear process systems. The coordinated-distributed control scheme proposed in this work benefits from using local model predictive controllers that can be coordinated to achieve the plantwide (centralized) optimal performance. The "price-driven" method is used to coordinate the local controllers. Newton's method, along with a sensitivity analysis technique, is used to update the price in the price-driven method. Convergence of the performance obtained with the CDMPC controllers to the plantwide optimal performance is shown. Simulation examples, including a forced-circulation evaporator process, are used to illustrate the effectiveness of the proposed coordinated-distributed control scheme.

a b s t r a c tIn this study we examined predation by small felids upon small and medium-sized prey mammals in the central region of the Monte Desert. We analyzed the degree of vulnerability of prey mammals in relation to their habitat use patterns, modes of locomotion and age classes. Medium and small rodents were the predominant prey in the diet of small cats. The most consumed small mammal was Akodon molinae, which inhabits areas of dense cover, while species occurring in open habitats such as Eligmodontia typus were less consumed. Among medium-sized mammals, Galea leucoblephara that depends on patches with high plant cover for refuge was more consumed than Microcavia australis that lives in colonies and displays a complex set of antipredator strategies. Prey selectivity on small rodents showed that E. typus, which uses bipedal locomotion and an erratic escape behaviour, was consumed in greater proportion than its availability. We suggest that although its specialized locomotory mode would diminish predator attacks, its preference for open habitats would increase the probability of predator-prey encounter. Consumption of small mammals focuses mostly on adult individuals. However, we found a significant consumption of senile individuals of A. molinae, which points out that vulnerability tends to be high towards the age of maturity in this species.

In this paper, a coordinated-distributed model predictive control (MPC) scheme is presented for large-scale discrete-time linear process systems. Coordinated-distributed MPC control aims at enhancing the performance of fully decentralized MPC controllers by achieving the plant-wide optimal operations. The 'price-driven' decomposition-coordination method is used to adjust the operations of the individual processing units in order to satisfy an overall plant performance objective. Newton's method, together with a sensitivity analysis technique, are used to efficiently update the price in the price-driven decomposition-coordination method. The efficiency of the proposed control scheme is evaluated using a model of a fluid catalytic cracking process.

In this paper, a coordinated-distributed model predictive control (CDMPC) scheme is proposed for discrete-time, linear, unconstrained dynamic systems. The proposed control scheme incorporates a coordinator that communicates with local CDMPC controllers. With the assistance of the coordinator, the local CDMPC controllers adjust their calculated control actions iteratively to achieve the optimal plant-wide operation. A 'prediction-driven' algorithm is used to coordinate the local CDMPC controllers. Convergence of the prediction-driven algorithm is shown along with a stability analysis of the closed-loop system under coordinated-distributed control. A simulation example is used to illustrate the effectiveness of the proposed coordinated-distributed control scheme.