ch11-Critical Chain Project Scheduling关键链项目进度计划

Chapter11

第11章CriticalChainProjectScheduling关键链项目进度计划11-01Aftercompletingthischapter,studentswillbeableto:通过本章学习，学生可以：Understandthedifferencesbetweencommoncauseandspecialcausevariationinorganizations.理解组织中常见普通原因偏差和特殊原因偏差之间的区别；Recognizethethreewaysinwhichprojectteamsinflatetheamountofsafetyforallprojecttasks.认识三种项目团队用来为所有项目任务提高安全量的方式；Understandthefourwaysinwhichadditionalprojecttasksafetycanbewasted.理解四种可能浪费附加项目任务安全的方式；11-02Chapter11LearningObjectives学习目标Distinguishbetweencriticalpathandcriticalchainprojectschedulingtechniques.区分关键路径和关键链项目进度计划技术；Understandhowcriticalchainmethodologyresolvesprojectresourceconflicts.理解关键链方法如何解决项目资源冲突；Applycriticalchainprojectmanagementtoprojectpriorities.把关键链项目管理方法应用到项目优先级的设定中。11-03Chapter11LearningObjectives学习目标TheoryofConstraints&

CriticalChainProjectScheduling

约束理论与关键链项目进度计划Aconstraintlimitsanysystem’soutput.

TheGoal–Goldratt约束限制任何系统的输出。

《目标》–高德莱特TOCMethodology

约束理论（TOC）Identifytheconstraint识别约束Exploittheconstraint利用约束Subordinatethesystem附属于系统Elevatetheconstraint打破约束Repeattheprocess重复过程11-04FIGURE11.2

FiveKeyStepsinTheoryofConstraintMethodology图11.2

约束理论(TOC)的五大核心步骤11-05Copyright©2013PearsonEducation识别系统约束利用系统约束附属于系统约束的其他一切约束打破系统约束重新评价系统Variation差异CommonCause普通原因Inherentinthesystem系统固有的SpecialCause特殊原因Duetoaspecialcircumstance归因于特殊的环境Managersshould

Understandthedifferencebetweenthetwotypes

理解两者之间的区别Notadjusttheprocessifvariationiscommoncause

若偏差由普通原因造成，则不需对项目做调整Notincludespecialcausevariationinrisksimulation

风险模拟中不要包括特殊原因偏差Notaggregatediscreteprojectrisks

不要聚合离散的项目风险11-06CCPMandtheCausesofProjectDelay

关键链项目管理(CCPM)和项目延时的原因Howsafetyisaddedtoprojectactivities

如何确保项目进度Individualactivitiesoverestimated

高估每项活动历时Projectmanagersafetymargin

项目经理安全边界Anticipatingexpectedcutsfrommanagement

预计高层管理减少成本time时间25%50%80%90%Gaussian(lognormal)Distribution高斯(对数正态)分布11-07WastingExtraSafetyMargin

丢失已获得的安全裕度TheStudentSyndrome学习综合症Immediatedeadlines快要截止日期的任务Paddedestimates增加了的时间预算Highdemand高需求Failuretopassalongpositivevariation积极偏差没有被传递Othertasks其它任务Overestimationpenalty过高的惩处Perfectionism完美主义Multitasking多任务交叉PathMerging路经汇聚11-08FIGURE11.6

StudentSyndromeModel

学习综合症模型

11-9Copyright©2013PearsonEducation“完美世界”模型学习曲线模型项目完成的百分比运行时间的百分比EffectsofMultitaskingonActivityDurations

多任务交叉对活动历时的影响11-10FIGURE11.7

Copyright©2013PearsonEducationFIGURE11.8

EffectofMergingMultipleActivityPaths

汇聚活动路径的影响11-11Copyright©2013PearsonEducation晚15天准时提前15天晚15天汇聚的路径CriticalChainSolutions关键链解决办法CentralLimitTheorem中心极限理论Activitydurationsestimatedat50%level以50%可能完成的概率，估计活动执行时间Bufferreappliedatprojectlevel

缓冲在项目层面的重新应用Goldrattruleofthumb(50%)高德拉特法则（50%）Newboldformula纽博尔德方程Feederbuffersfornon-criticalpaths

汇入缓冲用于非关键路径11-12CCPMChanges关键链项目管理(CCPM)的改进Duedates&milestoneseliminated消除了完工日期和里程碑的设置Realisticestimates–50%levelnot90%切合实际的估算—概率设置为50%而不是90%“Noblame”culture“无责备”文化Subcontractordeliveries&workscheduledES将分包商交付工作安排为最早开始时间NoncriticalactivitiesscheduledLS非关键活动安排为最晚开始时间Factortheeffectsofresourcecontention分解资源争用的影响Criticalchainusuallynotthecriticalpath关键链通常不是关键路径Solveresourceconflictswithminimaldisruption最低限度地解决资源冲突11-13CriticalChainSolutions关键链解决办法BobFeederBufferFeederBufferFeederBufferProjectBufferBobBobBuffersprotectconstraintsandpreventdelays

11-14汇入缓冲汇入缓冲汇入缓冲项目缓冲缓冲区能够保护限制并防止延误CriticalChainProjectPortfolios

关键链项目组合Drum–system-wideconstraintthatsetsthebeatforthefirm’sthroughput控制公司产出速度的鼓-全系统约束companypolicy公司政策oneperson一个人adepartment/workunit一个部门/工作单位aresource一项资源Capacityconstraintbuffer–safetymarginbetweenprojects能力约束缓冲—项目之间的安全裕度Drumbuffer–extrasafetybeforetheconstraint鼓缓冲—约束之前的瓶颈11-15ApplyingCCPMtoProjectPortfolios

把关键链项目管理应用到项目组合中Identifythedrum识别鼓Exploitthedrum利用鼓Prepareascheduleforeachproject制定每个项目的进度表Determinepriorityforthedrum确定每个鼓的优先级Createthedrumschedule创建鼓进度表Subordinatetheprojectschedules(nextslide)

附属于项目进度表（下一张幻灯片）Elevatethecapacityofthedrum提升鼓的能力Gobacktostep2返回第2步11-16SubordinatingProjectSchedules

附属于项目进度表Scheduleprojectsbasedondrum基于鼓制定项目进度表Designatecriticalchain指定关键链Insertcapacityconstraintbuffers插入能力约束缓冲Resolveanyconflicts解决任何冲突Insertdrumbuffers

sotheconstraintisnotstarved插入鼓缓冲则不至于缺乏约束11-17CCPMCritiques对关键链项目管理的批判Nomilestonesused未使用里程碑NotsignificantlydifferentfromPERT与计划评审技术(PERT)无明显差异Unprovenattheportfoliolevel在组合层面的应用未经证实Anecdotalsupportonly只受传闻支持Incompletesolution不完全的求解方法Overestimationofactivitydurationpadding高估活动历时边界值Culturalchangesunattainable文化变迁遥不可及11-18Summary总结Understandthedifferencesbetweencommoncauseandspecialcausevariationinorganizat