H_E, j, i = m_j ・ β ・γ_j,i ・cala

H_E, j, i : static substitute horizontal load
i          : Ordinal number of natural vibration form
j          : Number of mass point
m_j       : Mass of mass point j
               m_j  = (G_j + P_j) / g 
               G_j + P_j : Dead bad and live load of section j
β        : Coefficient of normalized response spectrum in function of natural vibration
             period (See Fig.1)
γ_j,i   : Coefficient of dynamic behavior of building in function of harmonic

ψ      : Deflection of mass points j in i-th harmonic (See Fig.2)
n        : Number of mass points
cala   : Calculated values of horizontal acceleration (See Fig.3, Table 1)