PERT时间参数计算(1)

活动紧前活动乐观估计a最大可能估计m悲观估计b均值方差A--12320.111BA23.5841CB6918104DC45.51061EC14.5540.444FE441051GD56.51171HEG581794IC37.5971JFI39981KJ44440LJ15.5751MH12320.111NKL55.5960.444=(C2+4*D2+E2)/6=(E222664abbma=(C2+4*D2+E2)/6=(E2-C2)*(E2-C2)/3622664abbma活动紧前活动均值ESEFLSLFS关键活动？A--202020YesBA426260YesCB106166160YesDC6162220264NoEC4162016200YesFE5202520250YesGD7222926334NoHEG9293833424NoIC7162318252NoJFI8253325330YesKJ4333734381NoLJ5333833380YesMH2384042444NoNKL6384438440YesT=44按均值估计完工期LFESLF=min{LS}LS=LF-tES=max{EF}EF=ES+tS=LF-EF=LS-ES活动紧前活动悲观估计bESEFLSLFSA--303030BA83113110CB18112911290DC10293929390EC5293430351FE10344435451GD11395039500HEG17506750670IC9293836457JFI9445345541KJ4535757614LJ7536054611MH3677067700NKL9606961701T=70按悲观估计完工期关键活动？YesYesYesYesNoNoYesYesNoNoNoNoYesNo31576关键路线：活动紧前活动乐观估计a最大可能估计m悲观估计b均值方差A--12320.111BA23.5841CB6918104DC45.51061EC14.5540.444FE441051GD56.51171HEG581794IC37.5971JFI39981KJ44440LJ15.5751MH12320.111NKL55.5960.444关键活动？Yesμ=44YesYesσ=9NoYesP{T≤T}=0.8413YesNo对给定的T=47NoNoYes若要P{T≤T}=0.95NoYesT=48.9NoYes均值关键路线20000时间(周)成本(万美元)正常极限正常极限A21$18$281$10B42$32$422$5C107$62$863$8D64$26$342$4E43$41$571$16F53$18$262$4G74$90$1023$4H96$20$383$6I75$21$272$3J86$43$492$3K43$16$201$4L53$25$352$5M21$10$201$10N63$33$513$6ProjectFinishTime40TotalCost$455活动最大加快时间(周)每加快一周的追加成本开始时间MaxTimeReduction=NormalTime-CrashTimeCrashCostPerWeekSaved=(CrashCost-NormalCost)/MaxTimeReductionFinishTime=StartTime+NormalTime-TimeReductionTotalCost=SUM(NormalCost)+sumprodict(CrashCostPerWeekSaved,TimeRe问题：在项目工期不超过希望水平的条件下，使总成本最小。需确定：1.每个活动的开始时间2.每个活动的加快时间241064579784526MaxTime=40万美元加快时间完成时间定义名称(1)NormalTimeC6:C19CrashTimeD6:D19NormalCostE6:E19CrashCostF6:F19MaxTimeReductionG6:G19CrashCostPerWeekSavedH6:H19StartTimeI6:I19TimeReductionJ6:J19FinishTimeK6:K19MaxTimeK22ProjectFinishTimeI22TotalCostI24定义名称(2)AFinishK6AStartI6BFinishK7BStartI7CFinishK8CStartI8DFinishK9DStartI9EFinishK10EStartI10FFinishK11FStartI11GFinishK12GStartI12HFinishK13HStartI13IFinishK14IStartI14JFinishK15JStartI15KFinishK16KStartI16LFinishK17LStartI17MFinishK18MStartI18NormalCost)/MaxTimeReductionTotalCost=SUM(NormalCost)+sumprodict(CrashCostPerWeekSaved,TimeRe约束(2)BStart≥AFinishCStart≥BFinishDStart≥CFinishEStart≥CFinishIStart≥CFinishFStart≥EFinishGStart≥DFinishHStart≥GFinishHStart≥EFinishJStart≥FFinishJStart≥IFinishKStart≥JFinishLStart≥JFinishMStart≥HFinishNStart≥LFinishNStart≥KFinish约束(1)TimeReduction≤MaxTimeReductionProjectFinishTime≤MaxTimeProjectFinishTime≥MFinishProjectFinishTime≥NFinish