design space pruning heuristics and global optimization method for ...
design space pruning heuristics and global optimization method for ...
design space pruning heuristics and global optimization method for ...
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identified as the 7 th best in the competition. The remaining competition solutions were<br />
eliminated during the <strong>pruning</strong> phase (none were pruned out by the branch-<strong>and</strong>-bound<br />
algorithm). Of note, three good sequences with J > 80 kg/yr (not identified by GTOC2<br />
competitors) were also found through application of this <strong>method</strong>ology. With additional<br />
computing resources or additional time, less stringent <strong>pruning</strong> metrics could have been<br />
selected, highlighting the trade between <strong>pruning</strong> strength <strong>and</strong> available computational<br />
resources.<br />
Table 24: Top seven solutions found by the <strong>method</strong>ology <strong>for</strong> the modified GTOC2 problem.<br />
Asteroid Sequence<br />
2004 UT1 – Echo –<br />
Concordia – Scholl<br />
2003 YN107 –<br />
Reginhald – Dido –<br />
1992 SU21<br />
2003 YN107 – Echo<br />
– Concordia –<br />
Scholl<br />
2003 YN107 –<br />
Chantal – Aglaja –<br />
1998 QB32<br />
2003 YN107 –<br />
Pilcher – Vanadis –<br />
Cunningham<br />
2005 QP11 –<br />
Chantal – Aglaja –<br />
1998 QB32<br />
2003 YN107 –<br />
Euterpe – Lydia –<br />
Tuckia<br />
Final<br />
Mass (kg)<br />
Time of<br />
Flight (yr)<br />
J<br />
(kg/yr)<br />
B&B<br />
Ranking<br />
898.2 9.11 98.64 #674<br />
829.0 9.52 87.05 #205<br />
761.9 8.81 86.54 #210<br />
834.8 9.67 86.29 #482<br />
835.2 9.78 85.43 #4467<br />
812.9 9.52 85.39 #476<br />
722.9 8.73 82.83 #785<br />
Notes<br />
#1 GTOC2<br />
competition<br />
#3 GTOC2<br />
competition<br />
New sequence<br />
identified in this<br />
investigation<br />
New sequence<br />
identified in this<br />
investigation<br />
#4 GTOC2<br />
competition<br />
Better solution to<br />
#7 GTOC2<br />
sequence<br />
New sequence<br />
identified in this<br />
investigation<br />
5.2.2 Full GTOC2 Problem<br />
The <strong>method</strong>ology is then applied to the full GTOC2 problem, using the same<br />
constraints as were given during the competition. The competition problem was released<br />
on November 6, 2006 <strong>and</strong> the deadline to submit results was December 4, 2006, a period<br />
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