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In a recent study a regime chart was established for sheared granular systems using discrete element simulations.For a soft particle system under simple shear the internal stress showed a range of rate dependency.As the particle concentration increased the system transitioned from a kinetic gas to a plastic solid.This transition was gradual for low stiffness particle systems but became more abrupt for high stiffness systems.The contour plot of the power index for the rate dependency consisted of a family of λ-shape curves.In this study, the relationship between the granular temperature and pressure is investigated for the same system of particles.The granular temperature is defined as the average kinetic energy per unit volume and the pressure is defined as the trace of the stress tensor.It is found that this pressure-temperature curve depicts a drastic turn when the rate dependency index drops below 1.That is, when the system moves away from the kinetic gas regime the pressure-temperature relation changes suddenly.However, no other signature is found in the P-T relationship in other regimes.In pursuit of an equivalent thermodynamic description for a dissipative system such as the sheared granular assembly, other quantities beyond pressure and temperature must be introduced.