DARPA ULTRALOG Final Report - Industrial and Manufacturing ...

Min-min heuristic algorithm
Step 1: Initialize a set of all unassigned clusters, U←J, and current machine-level completion
times, mc(k)←0 for all k∈K.
Step 2: Compute the minimal completion time after assignment for each unassigned cluster,
ωk
M={ min [ CLI j ( k ) + mc( k )]
k∈N
a
: j∈U}.
j ω
k
Step 3: Select the minimal from M, mmc←min M, and find corresponding cluster and
machine, c and m respectively.
Step 4: Assign c to m and update mc(m), mc(m)←mc(m)+mmc.
Step 5: Remove c from U.
Step 6: If U=∅ then go to step 7. Otherwise go to step 2.
Step 7: T * ← max mc( k ) .
k∈K
4. Empirical results
We ran several experiments through discrete-event simulation to validate the designed
method. Though we have not considered stochasticity so far, this empirical study will support the
effectiveness of the method even in stochastic environments.
4.1 Network description
The network is composed of eight components in four clusters as in Table 1. Task flow
structure between components is described in Fig. 2. There are three available machines {K 1 , K 2 ,
K 3 } with ω k =ω a k =1 for all k, and each cluster is assignable to any machine.
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