β
v n ( t , 0 )
∂ v n ∂ t ( t , 0 )
− ∞ < β < 0
v n ( t , 0 ) < 0
v n ( t , 0 ) → 0
t → ∞
∂ v n ∂ t ( t , 0 ) > 0
β = 0
v n ( t , 0 ) = 0
∂ v n ∂ t ( t , 0 ) = 0
0 < β < 3 2
v n ( t , 0 ) > 0
∂ v n ∂ t ( t , 0 ) < 0
β = 3 2
v n ( t , 0 ) = constant
3 2 < β < 5 3
v n ( t , 0 ) → ∞
β = 5 3
Exponentially
5 3 < β ≤ 2
t → t 1