"One can often divide the work a program does into conceptually separate tasks: each encapsulates a control flow and the entire task accesses some common, shared state. High-performance program often written with preemptive task management wherein execution of task can interleave on uniprocessors or over lap on multi processors. The opposite approach, serial task
Management, run each tasks to completion before starting the next task. Its advantage is that there is no conflict of access of the shared state, one can define inter-task invariant on the shared state and be assured that while the one task is running no other variants can violate the invariant. The strategy is inappropriate however when one wishes to exploit multiprocessors parallelism, or when slow task must not defer later task for a long time." (Adya, Howell, Theimer, Bolosky, Douceur, 2000)
"One of the major areas in any kind of enterprise, whether business, government, or others, is production and operations management.
It is also the area where managing as a scientifically based art got its start.
In the past, production management was the term used to refer to those activities necessary to manufacture products. However, in recent years, the area has been generally expended to include such activities as purchasing, warehousing, transportation, and other operations from the procurement of raw materials through various activities until a product is available to the buyer. The term operations management refers to activities necessary to produce and deliver a service as well as physical product. There are, of course, other essential activities undertaken by a typical enterprise. In addition to production, these enterprise functions often include research and development, engineering, marketing and sales, accounting, and financing.
Operations management systems
In the operations management model the inputs include needs of customers, information, technology, management and labor, fixed assets,