What is Cost-aware optimisation?

Cost-aware optimisation maximises $\alpha^\top w - \frac\gamma2 w^\top\Sigma w - C(w - w_0)$, with $C$ the cost model of the trade from the current book: here $C(d) = \sum_i s_i\lvert d_i\rvert + \eta\sigma_i\lvert d_i\rvert^{3/2}\sqrt{A/V_i}$ for half spreads $s_i$, a fund of size $A$ and daily traded values $V_i$.