New partial cooperation model for bilevel programming problems

Partial cooperation models are studied for many years to solve the bilevel programming problems where the follower’s optimal reaction is not unique. However, in these existed models, the follower’s cooperation level does not depend on the leader’s decision. A new model is proposed to solve this deficiency. It is proved the feasibility of the new model when the reaction set of the lower level is lower semicontinuous. And the numerical results show that the new model has optimal solutions when the reaction set of the lower level is discrete, lower semi-continuous and non-lower semi-continuous.

New partial cooperation model for ill-posed bilevel programming problem via satisfactory degree

Partial cooperation formulation is a more viable option than optimistic＇s and pessimistic＇s to solve an ill-posed bilevel programming problem.Aboussoror＇s partial cooperation model uses a constant as a cooperation index to describe the degree of follower＇s cooperation.The constant only indicates the leader＇s expectation coefficient for the follower＇s action,not the follower＇s own willingness.To solve this situation,a new model is proposed by using the follower＇s satisfactory degree as the cooperation degree.Then,because this new cooperation degree is a function which is dependent on the leader＇s choice and decided by the follower＇s satisfactory degree,this paper proves such proposed model not only leads an optimal value between the optimistic value and pessimistic＇s,but also leads a more satisfactory solution than Aboussoror＇s.Finally,a numerical experiment is given to demonstrate the feasibility of this new model.

Genetic-optimization framework for SVC transmission based on partial cooperative communication

A genetic-optimization framework based on the partial cooperation communication protocol is proposed for scalable video coding (SVC) stream transmission under multi-relay amplify and forward cooperative networks. Unlike traditional cooperative transmission schemes, the transmission mode for each coded unit in this new protocol can be switched flexibly between direct transmission and cooperative transmission. Obviously, under this protocol, the bandwidth efficiency and transmission robustness can be balanced adaptively according to the priority level of coded units and wireless channel fading characteristics. Based on this, a well-known genetic optimization algorithm-differential evolution is exploited here to find the jointly optimal transmission modes, power allocation and unequal error protection (UEP) channel coding strategies to minimize the end to end reconstructed video distortion. Extensive simulation results show that, compared with classical optimal cooperative UEP transmission schemes, the proposed optimized transmission framework based on the partial cooperative protocol can bring significant peak-signal-to-noise-ratio (PSNR) gains for the reconstructed video in a variety of channel bandwidth, power budget and test sequences.