项目管理双语教学课件：PM6 Developing a Project Plan

1、Project Management - 6Developing a Project PlanContent & objectivesTo establish the linkage between the WBS and the project networkTo diagram a project network using AON methodsTo provide a process for computing early, late, and slack activity times and identify the critical pathTo demonstrate under

2、standing and application of “lags” in compressing projects or constraining the start or finish of an activityTo provide an overview framework for estimating times and costs Developing the Project PlanThe Project NetworkA flow chart that graphically depicts the project activities that must be complet

3、ed, the logical sequence, the interdependencies, and in most cases the start and finish times of the project job, and the longest critical path through the network.Provides the basis for scheduling labor and equipment.Enhances communication among project participants.Provides an estimate of the proj

4、ects duration.Provides a basis for budgeting cash flow.Identifies activities that are critical.Highlights activities that are “critical” and can not be delayed.Help managers get and stay on plan. From Work Package to NetworkWBS/Work Packages to Network From Work Package to Network (contd)WBS/Work Pa

5、ckages to Network (contd) Constructing a Project NetworkTerminologyActivity: an element of the project that requires time.Merge Activity: an activity that has two or more preceding activities on which it depends.Parallel (Concurrent) Activities: Activities that can occur independently and, if desire

6、d, not at the same time.ACBD Constructing a Project Network (contd)TerminologyPath: a sequence of connected, dependent activities.Critical path: the longest path through the activity network that allows for the completion of all project-related activities; the shortest expected time in which the ent

7、ire project can be completed. Delays on the critical path will delay completion of the entire project.CABD(Assumes that minimum of A + B minimum of C in length of times to complete activities.) Constructing a Project Network (contd)TerminologyEvent: a point in time when an activity is started or com

8、pleted. It does not consume time.Burst Activity: an activity that has more than one activity immediately following it (more than one dependency arrow flowing from it).Two ApproachesActivity-on-Node (AON)Uses a node to depict an activity.Activity-on-Arrow (AOA)Uses an arrow to depict an activity.BDAC

9、 Basic Rules to Follow in Developing Project NetworksNetworks typically flow from left to right.An activity cannot begin until all of its activities are complete.Arrows indicate precedence and flow and can cross over each other.Identify each activity with a unique number; this number must be greater

10、 than its predecessors.Looping is not allowed.Conditional statements are not allowed.Use common start and stop nodes. Activity-on-Node Fundamentals Activity-on-Node Fundamentals (contd) Network Information Koll Business CenterPartial Network Koll Business CenterComplete Network Network Computation P

11、rocessForward PassEarliest TimesHow soon can the activity start? (early startES)How soon can the activity finish? (early finishEF)How soon can the project finish? (expected timeTE)Backward PassLatest TimesHow late can the activity start? (late startLS)How late can the activity finish? (late finishLF

12、)Which activities represent the critical path?How long can it be delayed? (slack or floatSL) Network Information Activity-on-Node Network Activity-on-Node Network Forward Pass Forward Pass ComputationAdd activity times along each path in the network (ES + Duration = EF).Carry the early finish (EF) t

13、o the next activity where it becomes its early start (ES) unlessThe next succeeding activity is a merge activity, in which case the largest EF of all preceding activities is selected. Activity-on-Node Network Backward Pass Backward Pass ComputationSubtract activity times along each path in the netwo

14、rk (LF - Duration = LS).Carry the late start (LS) to the next activity where it becomes its late finish (LF) unlessThe next succeeding activity is a burst activity, in which case the smallest LF of all preceding activities is selected. Determining Slack (or Float)Total slack (or float)The amount of

15、time an activity can be delayed without delaying the entire project.Total slack or float for an activity is simply the difference between the LS and ES (LS-ES=SL) or between LF and EF (LF-EF=SL) The critical path is the network path(s) that has (have) the least slack in common. Activity-on-Node Netw

16、ork with Slack Practical ConsiderationsNetwork Logic ErrorsActivity NumberingUse of Computers to Develop NetworksCalendar DatesMultiple Starts and Multiple Projects Illogical Loop Air Control Project Air Control Project (contd) Extended Network Techniques to Come Close to RealityLadderingActivities

17、are broken into segments so the following activity can begin sooner and not delay the work.LagsThe minimum amount of time a dependent activity must be delayed to begin or end.Lengthy activities are broken down to reduce the delay in the start of successor activities.Lags can be used to constrain fin

18、ish-to-start, start-to-start, finish-to-finish, start-to-finish, or combination relationships. Example of Laddering Using Finish-to-Start Relationship Use of LagsFIGURE 6.13Finish-to-Start RelationshipStart-to-Start Relationship Use of Lags ContdUse of Lags to Reduce Detail New Product Development Process Use of Lags (contd)Finish-to-Finish RelationshipStart-to-Finish RelationshipCombinationRelationshipNetwork Usi