Table 3. Phase II algorithm

Phase II algorithm: BFGS (Broyden-Fletcher-Goldfarb-Shanno)
Step 1: Set the initial value(Θ̃0) with Θ̃p1,10 (without Phase I, randomize the initial value)
Step 2: Iterate nonlinear optimization procedure (Convergence limit: Tolerance ≤ 0.00001)
 - Obtain the search direction (qk) with Hessian matrix(Hk, k: iteration number):
q k = H k f # ( T F , Θ ,   Θ ˜ k ,   Φ ) , q k 9 ,   H k 9 x 9 ,   f # 9
 - Calculate the step size(αk) by using golden section search technique:
α k = arg α   m i n   f #   ( T F , Θ ,   Θ ˜ k + α q k ,   Φ )  
 - Update new solution: Θ ˜ k + 1   =   Θ ˜ k + α k q k
 - Update Hessian matrix with the difference of gradients:
H k + 1       H k ,    α k q k ,    f # ( T F , Θ ,   Θ ˜ k + 1 ,   Φ ) f # ( T F , Θ ,   Θ ˜ k ,   Φ )
Step 3: Find the optimal solution → Θ ˜ o p t = Θ ˜ p 2