Managing Resources Program Evaluation and Review Technique (PERT) Production Process

Lecture content Identifying resources Apportioning resources – Gantt charts – Resource histogram Resource levelling Resource constraints

Recap on last week Scheduling Critical Path Analysis

Identifying resources People Services Facilities and equipment Supplies and materials Money

Resource considerations Cost estimates Availability Quality & output

Aim Need to maximise usage of resources Need to balance costs against early completion date Identify contingency

Apportioning resources Identify the resources needed for each activity Identify resource types Allocate resource types to activities and examine the resource histogram

Network diagrams A(15) B(12) C(7) D(34) F(18) E(28) G(14)

Information you need ActivityABCDEFG Imm. Pred. --AAB,C F Dur Float people

Gantt Chart

Resource Histogram Project Day No of people

Resource constraints You may have a restriction on the number of people you can put on a project. Questions – What happens to our project if we only have 14 people available at any given time? – Has making this adjustment changed the critical path of the project?

Resource Leveling a strategy used to correct resource over- allocations – task delaying – task splitting – Adding more resources

Time constraints You may be required to finish by a certain time. Question – What do you need to do to ensure your project ends by day 50 at the latest? – What is the most cost effective way to arrange this project to ensure it come in by day 50? – If each man costs £50 per day how much will your rescheduled project cost?

Other problems Need to allow for – Holidays – Sick leave You may need to pay for people even if you are not using them – therefore splitting up a job may be more effective

Objective of planning Feasibility assessment Resource allocation Detailed costing Motivation Co-ordination

EXTRA

The problem of resource scheduling in software projects ‘The mythical man-month’ originally written by Fredrick P Brooks in 1975 then revised in 1995 “Adding manpower to a late software project makes it later” “the man-month as a unit for measuring the size of a job is a dangerous and deceptive myth”

Mythical man-month explained People Months Time v. No or workers – Unpartitionable task People Months Time v. No or workers – Perfectly partitionable task

Mythical man-month explained People Months Time v. No or workers – Partitionable task requiring communication People Months Time v. No or workers – task with complex interrelationships

Answer to constraints question

Further Reading me/pmangt/samplecontent/520lesson08/less on08_01.html