SIMSCRIPT II.5 Programming Language

Discrete Simulation Concepts
1 process JOB
2 define TASK, REQUIRED as integer variables
3
4 until ROUTING.SET is empty
5 do
6 remove the first TASK from the ROUTING.SET
7 request 1 units of PRODUCTION.CENTER(TASK.DOER(TASK))
8 work TASK.DURATION.. HOURS
9 relinquish 1 units of PRODCUTION.CENTER(TASK.DOER(TASK))
10 destroy the TASK
11 loop
12
13 let CYCLE.TIME = TIME.V - ARRIVAL.TIME
14
15 end
This process models the complete life cycle of a job through the shop.
UNTIL
REMOVE
REQUEST
WORK
RELINQUISH
DESTROY
LOOP
Processing of this JOB is to continue until its ROUTING.SET is empty.
The first TASK in the set is removed for processing.
A MACHINE of type indicated by TASK.DOER is requested.
Execution of the requesting JOB process is suspended, if necessary, until a
MACHINE becomes available. While a particular JOB process is suspended,
other processes, including other instances of JOB process, will run using other
machines.
As no priorities are specified, a first-in-first-out discipline is provided whenever
more than one suspended process is waiting for the same type of resource.
Work on this JOB continues only when its MACHINE becomes available.
The JOB delays itself for a set time to model actual processing by a MACHINE.
The MACHINE is made available for other jobs.
Since this operation is complete, the TASK entity is destroyed.
Mark end of UNTIL loop.
Numeric results are gathered “on the fly” by accumulate and tally statements contained in
the Preamble. The final computation, is the total time, including delays, that it took to process
this job.
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