  The scaling properties of three-dimensional magnetohydrodynamic turbulence
are obtained from direct numerical simulations of decaying turbulence using
$512^3$ modes. The results indicate that the turbulence does not follow the
Iroshnikov-Kraichnan phenomenology.In the case of hyperresistivity, the
structure functions exhibit a clear scaling range yielding absolute values of
the scaling exponents $\zeta_p$. The scaling exponents agree with a modified
She-Leveque model $\zeta_p=p/9 + 1 - (1/3)^{p/3}$, corresponding to Kolmogorov
scaling but sheet-like geometry of the dissipative structures.

Fluid Dynamics;Plasma Physics