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EPQM – Resource Consideration. Lecture 8. EPQM. Introduction. PLC. Implementation. Proj Logistics. Quality. Introduction Attributes PLC Roadmap. Identify needs. Proj Planning. Proj Quality. Proj Team & Organization. Scheduling. Propose solution. Proj Comm & Documentation.
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EPQM – Resource Consideration Lecture 8
EPQM Introduction PLC Implementation Proj Logistics Quality • Introduction • Attributes • PLC • Roadmap Identify needs Proj Planning Proj Quality Proj Team & Organization Scheduling Propose solution Proj Comm & Documentation Controlling Perform the project Deliver Quality Event Risk Mgmt Resource Planning Terminate Cost Planning & performance
Needs Identification RFP Planning Scheduling Update Proj Schedule Controlling Decide which area need correction Calculate Time-cost Trade off Resources Planning
Lecture 7 Project must finish on time by adding resources Lecture 8 Resources are limited and project completion time must be extended. Focus of today’s lecture
Today’s Agenda • Taking resource constrains into account when developing a network diagram • Determine the planned resource utilization for a project • Leveling the use of resources within the required time frame • Determining the shortest project schedule with the limited resource available • Learn the problem solving skill in project management
A short Quiz • What is the meaning of slack? • Slack = LS-ES or LF - EF • Which activity should be given a top priority in accelerating the work? • The one with the lowest negative slack
Resource Constrained Planning (pg. 230) • The sequence of activities reflect the availability of a limited number of resources. Build Foundation Build frame Put on roof The 3 activities in serial relationship
Three relationship can be performed concurrently. Paint living room Activity sequence without resource constraints Start Project Finish project Paint kitchen Paint bedroom Suppose there is only one person available to do all the paintings Activity sequence based on resource constraints Start Project Paint living room Paint kitchen Paint bedroom Finish project
Planned resource utilization • It is necessary to indicate the amounts and types of resources needed to perform each activity. (pg. 232)
Resource utilization chart (pg. 233) Uneven utilization of labour. 4 painters 3 painters 2 painters 1 painter
Activity earliest start time as-soon-as-possible (ASAP) schedule. • Resource utilization charts based on each activity’s latest start time are said to be based on as-late-as-possible (ALAP) schedule.
Resource Leveling or Smoothing (pg. 232/233) • A method to minimize the fluctuations in requirements for resources. • It would be desirable to apply as uniformly as possible without extending the project schedule. • An activities can be delayed only to the point where all their positive slack is used up.
How to reduce resource sensibly without increasing the critical path? Method 1 – delay painting Basement room by 6 days and start after ‘Bedrooms’ are finished. xxxxxxxxxxxxxxxxxx Slack time = +8 days 3 3 3 3 3 3 3 3 3 3
Compare the Resource-leveled Profile for Painter before and after reallocating the resources. (pg. 233 & 235) 32 man days 4 labors 4 x 4 days = 16 man days 3 x 2 days = 6 2 x 4 days = 8 1 x 2 days = 2 32 man days 3 labors 3 x 10 days = 30 1 x 2 days = 2
How to reduce resource sensibly without increasing the critical path? (pg. 235) Method 2 – delay ‘Bedrooms’ so that it will start on day 4, after ‘Basement Rooms’ are finished. xxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxx Bedrooms (1 painter) 3 3 3 3 3 3 3 3 3 3
Conclusion • We see that the earliest start time for ‘Basement Rooms’ has been delayed from time 0 to day 6. • The earliest finish of ‘Basement Rooms’ is now day 10 (instead of the original Day 4) • With the delay of painting ‘Basement Rooms’ there is a more uniform utilization of painters though 32 days are still required to finish the work
Resource-Limited Scheduling(pg. 234) • A method for developing the shortest schedule when the number or amount of resources is fixed. • Extend the project completion time if necessary in order to keep within the resource limited.
Rules of Resource-Limited Scheduling (pg. 234) • An iterative (repetitive) method in which resources are allocated to activities based on the least slack. • When several activities need the same limited resource at the same time, the activities with the least slack have first priority. • If resources are left over, the activities with the second least slack have the next priority, and so forth. • If other activities need the resource but the resource have been totally allocated to higher-priority activities, the lower-priority activities get delayed; as their slack becomes worse, they eventually move up the priority ladder. • Result in extended project completion time.
The general principle (pg. 237/236) If only 2 painters were available, the project completion time needs to be extended from 12 days to 16 days.
Resource-Limited Schedule Process Normal process, but only 2 painters are available. How to determine which activity has priority? The answer is by looking at the slack. The lowest value is “First floor rooms” which is 0. This should be done first. Note “Basement rooms” has +8 days; “Bedrooms” has +6 days
Resource-Limited Schedule Process As a result, by pushing Basement and Bedroom forward, the project completion date has been extended by 2 more days to Day 14.
Resource-Limited Schedule Process But Day 9-10 still require 4 painters, exceeding the limitation of 2 painters. So, which activities should be carried out first? 2 days negative slack Original Deadline The answer should be the one with least slack i.e. Bedroom (-2) and Stairs (0) OR Basement (0).
Resource-Limited Schedule Process Stairs (0) OR Basement (0) should be completed first? Originally, Stairs has a slack of +8 days, and Basement has a slack of 0. Therefore, select Basement to be completed first.
Resource-Limited Schedule Process Now, Both Stairs and Bedrooms start on Day 9. As Basement and Bathroom has to start on Day 13, as a result, the project completion date has been extended to Day 16 Original Deadline Day 13 and 14 exceed the limit of 2 painters. What should be done?
Resource-Limited Schedule Process (pg. 239) Day 13 and 14 exceed the limit of 2 painters. What should be done? xxxxx Basement has a slack of -4 which is lower than Bathroom (-2), therefore, Bathroom should be postponed to Day 15 to keep the work in line with the limit of 2 painters.
Resource-Limited Schedule Process(pg. 239) The project completion time is still 4 days beyond the required project completion time, kept within the limit of 2 painters. Original completion date
Summary (pg. 240) • Resources can constrain the project schedule. • It is necessary to estimate the amounts and types of resources needed to perform each activity. • If sufficient resources are not available, some activities may have to be rescheduled for a later time when resources become available to perform the activities. • Resource leveling attempts to minimize the fluctuations in requirements for resources. It levels the resources so that they are applied as uniformly as possible without extending the project schedule beyond the required completion time. • Resource-limited scheduling develops the shortest schedule when the number of resources is fixed. It will extend the project completion time if necessary in order to keep within the resource limit.