Project “A project is a series of activities directed to accomplishment of a desired objective.”Work break down structure “Project can be splitted into small tasks with sequence of the their execution. This process is known as work break down structure “ Plan your work first…..then work your plan
Network analysisNetwork analysis is the general name given to certain specifictechniques which can be used for the planning, management andcontrol of projects.Main objectives are:1. Complete the project within stipulated period..2. Optimize resources utilization.3. Better coordination in interdependent activitiesC.P.M & P.E.R.T are two methodologies to analyze the network
PERT - Project Evaluation & Review Techniques Definition: In PERT activities are shown as a network of precedence relationships in which successive events are joined by arrows. – Probabilistic activity times – Optimistic time, pessimistic time, most likely time. – Event oriented diagram USED IN : Project management - for non-repetitive jobs (research and development work), where the time and cost estimates tend to be quite uncertain. This technique uses probabilistic time estimates.
CPM - Critical Path Method Definition: CPM activities are shown as a network of precedence relationships in which successive activities are represented by arrows. .also called PPS – Single estimate of activity time – Deterministic activity times – Activity oriented diagram USED IN : Production management - for the jobs of repetitive in nature where the activity time estimates can be predicted with considerable certainty due to the existence of past experience.
Terminologies used in C.P.M Use of nodes and arrows Arrows An arrow leads from tail to head directionally – Indicate ACTIVITY, a time or resource consuming effort that is required to perform a part of the work. – Direction of the progress of the project Nodes A node is represented by a circle - Indicate EVENT, a point in time where one or more activities start and/or finish. - Some part of the project has been complete - Merge events, brust events.
Terminologies used in C.P.M Relation ship between Events: 1. Successor Events 2. Predecessor Events Activity: 1. Successor Activity 2. Predecessor Activity 3. Dummy Activity 4. Concurrent Activity
Activity on Node & Activity on ArrowActivity on Node Activity on Arrow- A completion of an activity - An arrow represents a task, is represented by a node while a node is the completion of a task - Arrows represent order of events
Rules to draw the network1. Each event is presented by the nodes & activity by an arrow2. The starting event should be represented by i3. The completion of project should be assigned highest number in the network4. The activities emerging from event i should have no predecessor activities & event having highest number in diagram should have no successor activity5. The activity must have highest number for its head (arrow) than its tail6. Network diagram cannot have more than one starting node or end node
Rules to draw the network7. 7. There should not be a loop in diagram8. 8. An event cannot occur or an activity cannot start unless all its preceding activities have been completed (not applicable on dummy activity )
Fulkerson’s RuleThe starting event(having no predecessor activity isnumbered as 1 ) other events are numbered in increasingorder from 1 to rightwards , if there are more then 1initial event found in a diagram , anywhere they are to benumbered fro top to bottom in increase order no twoevents can have the same number in any case
Question 1Activity Predecessor A --- B A C B D C,E E B F C,E G F H G I H,D J IDraw the network diagram
Question 2A project consist of 7 activities .Activities P,Q,R run simultaneously . The relationship among the various activities is as followActivity successor P S Q T R UActivity V is the immediate successor to S, T, & UDraw the network diagram
Question 3Activity Predecessor A --- B --- C A D C E A F E G B H G I C,E J F K D,G,JDraw the network diagram
Estimation activity time Most optimistic completion time Most pessimistic completion time Most likely completion time te = a+4m+b 6 Where, a = Most optimistic completion time b = Most pessimistic completion time m = Most likely completion time
Question 4Q: Draw the network, labeling activitiesJob Activity Immediate Optimistic time Most likely Pessimistic time Predecessor a m b A - 5 6 7 B - 2 5 8 C A 6 7 14 D B 1 2 3 E C, D 3 3 3 F B 6 8 10 G E 1 4 7 H F, G 4 5 6
Activity Slack- Earliest starting time (EST) , which is a calendar time when a event can occur when all the predecessor events completed at the earliest possible times- Earliest finish time (EFT)- * Preceding from start to finish
Activity Slack- Latest starting time (LST): The latest time by which an activity is started with out delaying the total project completion.- Latest finish time (LFT): * Start working from finish to start
Determination of critical pathCritical Path: Critical path is the series of connecting activities from starting to end for which the total time of completion of all activities is maximumCritical activities /Bottle neck :All activities come in the way of critical path are called critical activitiesNon Critical activities : All activities do not come in the way of critical path are called non critical activities
Float/ Slacks Slack is the amount of time an event can be delayed without delaying the project completion Positive slack Negative slack Zero slack Slack = LST – EST LFT – EFT
Question 4Activities Predecessor activities Activity Time L ---- 3 M ---- 4 N L 9 O L 3 P O 3 Q N,M 6 R N,M 4 S R 2 T R 5 U P,Q,S 6Draw the network diagram Calculate EST,EFT,LST,LFT ,activity slack &high light the critical path
Crash TimeCrash time = Crashed Cost – Normal Cost Normal Time – Crashed Time
Normal Question 5 Crash Nodes Time Cost Time Cost 1-2 3 300 2 400 2-3 3 30 3 30 2-4 7 420 5 580 2-5 9 720 7 810 3-5 5 250 4 300 4-5 0 0 0 0 5-6 6 320 4 410 6-7 4 400 3 470 6-8 13 780 10 900 7-8 10 1000 9 1200Project indirect cost is 50Rs. Per week. Draw the network diagram &identify the critical path ? What are the normal project duration andassociated Cost ? Find total float associated with each activityCrash the relevant activities systemically and determine the optimalproject completion and cost
Question 6 On May 1,Arnie Watson sent a memo to his boss, the director of the project (6) management. Stating that the MX project would require 13 weeks for the completion. Arnie realized that customer wanted the job completed in less time, after discussions with the functional managers,Arnie developed the table shown. According to the contract there is a penalty payment of $5,000 per week for every week over six. What is the minimum amount of additional funding that arnie should request.
Normal CrashJob Activity Predecessor Time Cost ($.) Time Cost ($.) Activity A - 3 6,000 2 8,000 B A 5 12,000 4 13,500 C A 5 16,000 3 22,000 D A 4 8,000 2 10,000 E C,D 2 6,000 1 7,500 F B,E 3 14,000 1 20,000
Benefits of CPM/PERT Interdependencies of activity Project completion time Impact of late start Impact of early start “what if “ exercise Evaluation of performance
Questions Answered by CPM & PERT Completion date? On Schedule? Within Budget? Critical Activities? How can the project be finished early at the least cost?
Limitations to CPM/PERT Clearly defined, independent and stable activities Specified precedence relationships Over emphasis on critical paths