A New Model-independent Method of Determinating |V_ub/V_cb| and |V_ub|

In order to determine the ratio of CKM matrix elements $|V_{ub}/V_{cb}|$ ~(and $|V_{ub}|$), we propose a new model-independent method based on the heavy quark effective theory, which is theoretically described by the phase space factor and the well-known perturbative QCD correction only. In the forthcoming asymmetric $B$-experiments with microvertex detectors, BABAR and BELLE, the total separation of $b \rightarrow u$ semileptonic decays from the dominant $b \rightarrow c$ semileptonic decays would be experimentally viable. We explore the possible experimental options: the measurement of inclusive hadronic invariant mass distributions, and the `$D - \pi$' separation condition. We also clarify the relevant experimental backgrounds.