  Motivated by the recent experiments reporting the doping dependence of the
short-range charge order (CO) in electron-doped cuprates, we study the resonant
x-ray scattering spectrum from d-wave bond-charge fluctuations obtained in the
two-dimensional t-J model. We find that (i) the CO is short-range, (ii) the CO
peak is pronounced at low temperature, (iii) the peak intensity increases with
decreasing carrier doping $\delta$ down to $\delta \approx$ 0.10 and is
substantially suppressed below $\delta \approx$ 0.10 due to strong damping, and
(iv) the momentum of the CO decreases monotonically down to $\delta \approx$
0.10 and goes up below $\delta \approx$ 0.10. These results reasonably capture
the major features of the experimental data, and the observed short-range CO
can be consistently explained in terms of bond-charge fluctuations with an
internal d-wave symmetry.
