  We develop n-cluster mean-field theories (0 < n < 5) for calculating the flow
properties of the non-equilibrium steady-states of the Katz-Lebowitz-Spohn
model of the driven diffusive lattice gas, with attractive and repulsive
inter-particle interactions, in both one and two dimensions for arbitrary
particle densities, temperature as well as the driving field. We compare our
theoretical results with the corresponding numerical data we have obtained from
the computer simulations to demonstrate the level of accuracy of our
theoretical predictions. We also compare our results with those for some other
prototype models, notably particle-hopping models of vehicular traffic, to
demonstrate the novel qualitative features we have observed in the
Katz-Lebowitz-Spohn model, emphasizing, in particular, the consequences of
repulsive inter-particle interactions.
