In the six-quark model with the gauge group $SU(2)_L\times{SU}(2)_R\times{U}(1)$, and left-right symmery, we obtain four physically acceptable mass matrices which are different from the ones known so far by imposing the specific conditions for the coupling constants of a quark-Higgs-boson Yukawa interaction on the assumption that the interaction is invariant under the most general discrete transformation. However, only the two of these mass matrices are possible from the recent result of the lift-time experiments on the b-quark. The extented Cabibbo current with CP-violation is expressed in terms of quark mass ratios and phases in the quark mass matrices. It is predicted that t-quark mass is order of 50 Gev and an upper limit for T-neutrino mass is 9 MeV.
Gauge 군의 구조가 $SU(2)_L \times SU(2)_R \times U(1)$ 인 Six-Quark Model과 좌우 대칭성으로 고찰하여, 물리적으로 받아들일수 있는 4가지 Mass Matrices 를 도출하였다. 이에따라 t-quark 의 질량은 50 GeV 정도가 되어야 함을 분명히 하였을 뿐만 아니라, tau-neutrino $(\nu_{\tau})$의 질량의 상한은 9 MeV가 된다는 것도 아울러 밝혀냈다.
