ogonalapproximationyieldingastockutilizationof.;and(g)layoutgeneratedbyusingCNAyieldingastockutilizationof..timetakentoestimateasuitablerotationangleforthepatternsisalwaysmuchlonger.Inordertoincreasetheaccuracyandspeedofnesting,ChengandRao[]proposedacompactneighborhoodalgorithm(CNA)thatconsiderstherelationshipbetweenthenumberofneighborsandthesharingspacebetweenthem.Fig.gshowsatypicallayoutgeneratedusingCNAwhichnormallyyieldshigherpackingdensitywhencom-paredwiththeorthogonalandhexagonalapproximations.However,CNA,initspresentform,hasbeenmainlydesig-natedfornestingofpatternswiththeconsiderationoffullorientationconstraints,andisnotidealforsituationswheremorefreedomisavailableintheorientationofpatterns.ThisstudyisaimedatimprovingtheexibilityofCNAbyincorporatingtheavailablefreedomintheorientationofpatternsandageneticalgorithm(GA)thatfollowsnaturalrulestooptimizethegeneratedlayo势。
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