lower usage by one unit beginning on day 21 (remember that we have already delayed f one day), and increase usage by one unit beginning on day 35, continuing to the end of the project. This action increases peak use of B from nine to ten units.
It is important to emphasize that if the network under consideration is more complex and the number of resources to be leveled is realistically large, a manual leveling process is out of the question. Computer-aided leveling is not only mandatory, it is also helpful because it allows the PM to experiment with various patterns of resource usage through simulation.
In the next section we raise the most general problem of minimizing resource usage while still achieving various completion dates—or the inverse problem, minimizing completion times while operating with specified limits on resources.
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The Sacramento Municipal Utility District had been using color-coded magnetic scheduling boards for over 20 years to keep track of line construction, meter, and service job status for its 426,000 customers and to make daily crew assignments. But with explosive population growth and increased systems maintenance requirements, the system was overloaded, resulting in a backlog of over 3000 line construction jobs. Thus, a new, computerized forecasting, planning, scheduling, and monitoring system was needed. Management dictated three requirements: (1) Keep it simple, (2) Allow for future expansion, and (3) Assure compatibility with existing information systems.
The project proceeded in phases:
Definition—managerial interviews and analysis of needs
Design and approval of action plan—work scope, resource requirements, schedule Information gathering—interviews with working personnel
Analysis and documentation—constructing CPM schedules, process flowcharts, data dictionaries System specification—specifications and programming
Data loading and testing—issuing status reports and meeting to resolve problems Documentation and training—provide for later in-house modification ability.
Schedule construction is now a two-step process (see figure). First, CPM schedules are loaded into the system for each construction project. Second, the program reschedules the jobs based on priorities and worker availability, always maintaining customer-required dates. Any conflicts are worked out by a central planning/scheduling group with line management and the customer.
To gain scheduler acceptance, a one-month trial period was undertaken to get feedback about the system. Indeed, comments from the schedulers led to a change in the manner of scheduling on the computer, as well as some significant customization of the report-writing capabilities of the system. However, with these changes the system was well accepted by the users.
Source: C. I. Pospisil, "A PC-Based Scheduling System for a Transmission and Distribution Construction Department," Project Management journal, Sept. 1990.
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What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.