Basic concepts of network analysis

2,107 views

Published on

Published in: Education, Technology, Business
0 Comments
3 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
2,107
On SlideShare
0
From Embeds
0
Number of Embeds
547
Actions
Shares
0
Downloads
45
Comments
0
Likes
3
Embeds 0
No embeds

No notes for slide

Basic concepts of network analysis

  1. 1. Network Analysis • Network analysis is the general name given to certain specific techniques which can be used Basic Concepts of Network for the Analysis – planning, Presented by: – management and Anupam Kumar – control Reader School of Management Sciences, Varanasi • of projects. Email: anupamkr@gmail.com © Copyright 2013 Anupam Kumar 1 © Copyright 2013 Anupam Kumar 2 Project Project Management • Project is a temporary endeavour undertaken • A big project usually have many activities and to create a unique product – certain activities can begin only when – some specific activities are completed. – Project are unique undertakings • It is in the interest of the organization to have a – Project are composed of interdependent activities comprehensive study of the entire project in – Project create quality deliverables terms of – Project involve multiple resources – precedence and succession of various activities – Projects are not synonymous with the products of – as well as resource available the project – to perform these activities – Projects are driven by competing constrains – with an objective to evolve some better and quick plan to complete work. © Copyright 2013 Anupam Kumar 3 © Copyright 2013 Anupam Kumar 4 Project Evaluation Project Management & Control • The most commonly used project evaluation chart had been the Gantt Chart. • However Gantt Chart does not clearly indicate • They provide an easy graphical representation of when – details regarding the progress of activities activities (might) take place. – interrelation ship between the separate activities • These deficiencies can be eliminated to a large extent by showing the interdependence of various activities by means of connecting arrows. • This technique is called network technique. © Copyright 2013 Anupam Kumar 5 © Copyright 2013 Anupam Kumar 6© Copyright 2013 Anupam Kumar 1
  2. 2. Project Network Activity in Arrow and Node • The Project Network is shown with the help of Activity on Arrow Activity on Node Arrows & Nodes like: Arrows An arrow leads from tail to head directionally - An arrow represents a - A completion of an – Indicate ACTIVITY, a time consuming effort that is required to perform a part of the work. task, while a node is the activity is represented completion of a task by a node Nodes n A node is represented by a circle - Arrows represent order of events - Indicate EVENT, a point in time where one or more activities start and/or finish. © Copyright 2013 Anupam Kumar 7 © Copyright 2013 Anupam Kumar 8 Terms used in Network Analysis Numbering of Events • Precessor Activity • Optimistic Time • Every activity in the network is defined by its start and end – An activity that must occur – Time for completing an activity if events. The numbering is done in ascending order. before another activity. all goes well. – Initial Start Event is numbered first. • Successor Activity • Pessimistic Time – All arrows beginning in this event are crossed. – An activity that must occur after – Time for completing an activity if another activity all goes wrong. – Put next higher number for particular event where only crossed • Dummy Activity • Most Likely Time arrows end. – An activity that consumes no – Time for completing an activity time but shows precedence that is the consensus best 4 7 between events. estimate. • Activity Duration • Expected Time – In CPM: the best estimate of the – Average time for completing an time to complete an activity activity 1 2 5 – In PERT: the expected or average time to complete an activity. © Copyright 2013 Anupam Kumar 9 3 6 © Copyright 2013 Anupam Kumar 10 Illustration Activity Slack • A particular job operation in a plant undergoes the following • Each event has two important times associated with it : processes A, B, C, D, E & F along with time each activity takes - Earliest time , TE, which is a calendar time when a event can occur in weeks. when all the predecessor events completed at the earliest possible – How much time is required for the inventory to be ready for sale? times – Can some activity start at a later time, as this would help optimize the - Latest time , TL , which is the latest time the event can occur with out manpower resources? delaying the subsequent events and completion of project. B • Difference between the latest time and the earliest time of an E event is the slack time for that event 1 7 Inventory A C F For Sale – Positive slack : Slack is the amount of time an event can be delayed without delaying the project completion D © Copyright 2013 Anupam Kumar 11 © Copyright 2013 Anupam Kumar 12© Copyright 2013 Anupam Kumar 2
  3. 3. Calculating the Slacks Total Float or Total Slack B • It is the amount of time an activity can be delayed 2 4 E beyond its earliest possible starting time without delaying the project completion if other activities 6 8 1 take their estimated duration. C 7 Inventory A F For Sale • It gives the indication of the criticality of an activity. 1 3 • An activity with little float stands a good chance of 0 0 11 11 delaying the project and should be carefully D monitored. Total float for activity (i-j) = LE (j) – EE (i) – D; 6 6 Where LE is Latest Event Time, EE is Earliest Event Time and © Copyright 2013 Anupam Kumar 13 D is Duration. © Copyright 2013 Anupam Kumar 14 Free Float or Free Slack Independent Float or Slack • It is the amount of time an activity can be delayed • It is the time span by which an activity can be without delaying the early start of a successor expanded or shifted such that the latest time of the activity. preceding activity and the earliest time of the Free Float for activity (i-j) = EE(j) – EE(i) – D; succeeding activity is maintained. Where LE is Latest Event Time, EE is Earliest Event Time and • A shifting of the activity in this area has no influence D is Duration. on the further progress of the project. 1 If D > ((EE(j) – LE(i)) then: C 7 Inventory A F For Sale Independent Float(i-j) = EE(j) – LE(i) – D, else 1 3 0 0 11 11 Independent Float(i-j) = 0; where LE is Latest Event Time, EE is Earliest Event Time and D is Duration. © Copyright 2013 Anupam Kumar 15 © Copyright 2013 Anupam Kumar 16 Calculate the Slacks for activity C-E Calculate the Activity Slacks B 2 3 4 A D E F E 2 4 8 6 8 1 C 7 2 Inventory A F For Sale O B G K 3 1 4 5 0 0 11 11 4 I J 1 D 2 Total Slack = 8 – 1 – 4 = 3 C H Free Slack = 6 – 1 – 4= 1 6 6 Independent Slack = 6 – 4 – 4 = (-2) Independent Slack = 0 © Copyright 2013 Anupam Kumar 17 © Copyright 2013 Anupam Kumar 18© Copyright 2013 Anupam Kumar 3
  4. 4. Calculating Activity Slack Critical Path 0 2 2 5 5 9 9 17 • Critical Path is that the sequence of activities 0 2 2 2 3 5 5 4 9 9 8 17 and events where there is no “slack” i.e.. – Zero slack 0 2 2 5 3 2 5 5 3 8 • Critical Path is the 5 9 9 14 – Longest path through a network 8 4 12 12 5 17 – Path having maximum project completion time 0 2 2 3 Total Slack (j) 5 2 7 7 1 8 Free Slack (j) Independent Slack (j) © Copyright 2013 Anupam Kumar 19 © Copyright 2013 Anupam Kumar 20 Bibliography • Buffa, E.S. and Sarin, R.K., “Modern Production/Operations Management,” Eighth Edition. Singapore: John Wiley & Sons (Asia). 1994. • Martinich, J.S., “Production and Operations Management: An Applied Approach”, Singapore: John Wiley & Sons (Asia), 2003. • Badi, R.V. and Badi, N.V., “Production and Operations Management”, Second Edition, New Delhi: Vrinda Publication, 2008. For further details… • Chary, S.N., “Productions and Operations Management,” Third Edition, New Delhi: Tata McGraw Hill, 2004 • Goel, B.S., “Production Operations Management”, Twenty Second Edition, Meerut, U.P.: Pragati Prakashan, 2010. • Kachru, U. “Production and Operations Management: Text and Cases,” New Delhi: Excel Books, 2007. Contact: • Rama Murthy, P., “Production and Operations Management,” New Delhi: New Age International, Anupam Kumar 2012. • Chunawalla, S.A., and Patel, D.R., “Production and Operations Management,” Mumbai: Himalaya Reader Publishing House, 2006. School of Management Sciences, Varanasi • Jauhari, V. and Dutta, K., “Services: Marketing Operations and Management,” New Delhi: Oxford University Press, 2010. Email: anupamkr@gmail.com • Verma, H.V., “Services Marketing: Text and Cases,” New Delhi: Dorling Kindersley, Pearson Education, 2009. © Copyright 2013 Anupam Kumar 21 © Copyright 2013 Anupam Kumar 22© Copyright 2013 Anupam Kumar 4

×