Software Engineering

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CHAPTER 8 
Software Requirements Analysis Practice
6. 
Duration
—each of the operational activities consumes time and when the oper-
ational model is analyzed the operational timeline can be generated to express 
how long the operational process takes to execute. Since the objective of most 
automation programs is to make the process more effective, less costly, and con-
ducted more rapidly, it is important to understand the existing process execution 
time and the improvement in performance expected when the software product 
is involved.
7. 
Resources
—operational activities may require that resources be available for 
an operational activity to be performed. The unavailability of a needed resource 
will cause the activity to be placed into a wait-state until the resource is made 
available. Resources can be of the following types:
●
 
Consumable
—a resource that is used up when the operational activity is 
conducted. Resources that are consumed must have an initial amount that is 
available, the maximum amount that can be on hand at any one time (inven-
tory capacity), and the amount that is consumed by the activity. An ATM 
has a supply of money that it can dispense. Each withdrawal transaction 
decrements the amount of money available to be dispensed as a consumable 
resource.
●
 
Reusable
—a resource that is captured by an operational activity and is 
released by the activity when it is done executing. A cash register is a reus-
able type of resource, and only one sales associate can conduct a transaction 
using a register at a time.