University:
California State University, Northridge
Course:
MSE 402 | Engineering Project Management
Academic year:

2024
Views:

434

Pages:

19
Author:

Makhi Crane

Scheduling Resources and Costs Part 1 Where We Are Now The Resource Problem • Resources and Priorities –Project network times are not a schedule until resources have been assigned. • The implicit assumption is that resources will be available in the required amounts when needed. • Adding new projects requires making realistic judgments of resource availability and project durations. –Cost estimates are not a budget until they have been time-phased. Project Planning Process FIGURE 8.1 The Resource Problem (cont’d) • Resource Smoothing (or Leveling) –Involves attempting to even out varying demands on resources by using slack (delaying noncritical activities) to manage resource utilization when resources are adequate over the life of the project. • Resource-Constrained Scheduling –The duration of a project may be increased by delaying the late start of some of its activities if resources are not adequate to meet peak demands. Types of Project Constraints • Technical or Logic Constraints – Constraints related to the networked sequence in which project activities must occur. • Physical Constraints – Activities that cannot occur in parallel or are affected by contractual or environmental conditions. • Resource Constraints – The absence, shortage, or unique interrelationship and interaction characteristics of resources that require a particular sequencing of project activities • Kinds of Resource Constraints – People, materials, equipment Constraint Examples FIGURE 8.2 Classification of A Scheduling Problem • Classification of Problem –Using a priority matrix will help determine if the project is time or resource constrained. • Time-Constrained Project –Must be completed by an imposed date. • Time is fixed, resources are flexible: additional resources are required to ensure project meets schedule. • Resource-Constrained Project –Is one in which the level of resources available cannot be exceeded. • Resources are fixed, time is flexible: inadequate resources will delay the project. Resource Allocation Methods • Limiting Assumptions –Splitting activities is not allowed—once an activity is start, it is carried to completion. –Level of resources used for an activity cannot be changed. • Risk Assumptions –Activities with the most slack pose the least risk. –Reduction of flexibility does not increase risk. –The nature of an activity (easy, complex) doesn’t increase risk. Resource Allocation Methods (cont’d) • Time-Constrained Projects –Must be completed by an imposed date. –Require use of leveling techniques that focus on balancing or smoothing resource demands. –Use positive slack (delaying noncritical activities) to manage resource utilization over the duration of the project. • Peak resource demands are reduced. • Resources over the life of the project are reduced. • Fluctuation in resource demand is minimized. Botanical Garden FIGURE 8.3 Resource Allocation Methods (cont’d) • Resource Demand Leveling Techniques for Time-Constrained Projects –Advantages • Peak resource demands are reduced. • Resources over the life of the project are reduced. • Fluctuation in resource demand is minimized. –Disadvantages • Loss of flexibility that occurs from reducing slack. • Increases in the criticality of all activities. Resource Allocation Methods (cont’d) • Resource-Constrained Projects – Resources are limited in quantity or availability. – Activities are scheduled using heuristics (rules-of-thumb) that focus on: 1. Minimum slack 2. Smallest (least) duration 3. Lowest activity identification number – The parallel method is used to apply heuristics • An iterative process starting at the first time period of the project and scheduling period-by-period the start of any activities using the three priority rules. Resource-Constrained Schedule through Period 2–3 FIGURE 8.4 Resource-Constrained Schedule through Period 2–3 FIGURE 8.4 (cont’d) Resource-Constrained Schedule through Period 2–3 FIGURE 8.4 (cont’d) Resource-Constrained Schedule through Period 5–6 FIGURE 8.5 Resource-Constrained Schedule through Period 5–6 FIGURE 8.5 (cont’d) Resource-Constrained Schedule through Period 5–6 FIGURE 8.5 (cont’d)