Single-timescale distributed GNE seeking for aggregative games over networks via forward-backward operator splitting

We consider aggregative games with affine coupling constraints, where agents have partial information on the aggregate value and can only communicate with neighbouring agents. We propose a single-layer distributed algorithm that reaches a variational generalized Nash equilibrium, under constant step sizes. The algorithm works on a single timescale, i.e., does not require multiple communication rounds between agents before updating their action. The convergence proof leverages an invariance property of the aggregate estimates and relies on a forward-backward splitting for two preconditioned operators and their restricted (strong) monotonicity properties on the consensus subspace.Comment: 8 pages, 8 figures, submitted to TA

Nash Equilibrium Seeking Over Undirected Graphs Via Multi-Agent Agreement

We consider the problem of distributed Nash equilibrium seeking over networks. In this setting, agents have limited information about the other players' actions and are forced to communicate with neighbouring agents. We start with a continuous-time gradient-play dynamics, with perfect information, under a strictly monotone pseudo-gradient assumption. In the partial information case we modify the gradient-play dynamics between players by expanding the action space. We propose an augmented gradient-play dynamics in which players can only communicate locally with their neighbours to compute an estimate of the other players' actions. We derive new dynamics based on the reformulation of the problem as a multi-agent coordination problem, over an undirected graph. We exploit the incremental passivity properties in the dynamics and show that a Laplacian feedback can be designed using relative estimates of their neighbours. We highlight that there is a trade-off between properties of the game and the communication graph.M.A.S

Nanosize LiNiyMn2 - yO4 (0 < y ≤ 0.5) spinels synthesized by a sucrose-aided combustion method. Characterization and electrochemical performance

Nanosize crystalline cathode materials of LiNiyMn2 - yO4 (0 100 nm). Electrical conductivity decreases as the Ni content increases in accordance with an electron hopping mechanism between Mn3+ and Mn4+ ions. The 500°C- and 800°C-heated LiNi0.5Mn 1.5O4 samples show good electrochemical behaviour at 4.7 V as cathode materials. The capacity (132.7 mA h g-1) found is close to the nominal capacity (146.7 mA h g-1) and remains constant for current densities in the range C/24-2C (where C = 2.6 mA cm-2). At higher current densities (2C-10C) the capacity decreases progressively. The cyclability at the C current density is ca. 99.7% for both samples.Financial support by MCyT (Project MAT 2001-0562) is gratefully acknowledged. M. G. Lazarraga thanks the MECD for a fellowship. K. Petrov thanks the MECD for a sabbatical grant (SAB 2002-0002)