X - UWSpace - University of Waterloo

from the same aggregated subproblem as shown in figure 4.2 in the previous section. Lads
serial method solves the firsr subproblem and sends prima1 information to the second
subproblem. then it solves the second subproblem and sen& prima1 information to the third
subproblem. By doing the same procedure to the third subproblem. Lm's method solves the
lut subproblem and sen& back dual information to the third subproblem and continues to
solve and send dud information as in the following figure. thus shows its nature of senal
computation.
Figure 4.4 Information flow of 4-stage decomposition in Lads method.
When the iteration counter b l, s&~' , in which j* denotes the second level iteration
counter satisfying the stopping critena of level Il. Le. - 5 E or =iJ I , gives upper
bounds ro the original problem and s&'. in which i' denotes the second level iteration
counter satisfying the stopping criteria of level II, i.e. - L:J < E or 5 ;:.I , provides lower
61