Simulation, use when
A system decision is being made
system is definable and repetitive (sort of)
Activities and events are interdependent and are variable
Cost to experiment on the actual system is greater than the cost of simulation
Queuing science
single server, single phase/step
more than one server, single phase/step
single server, more than one phase/step
more than one server, more than one phase/step
Balking (not enter queue), Reneging (in queue, but leaves before being served), jockeying (move
from line to line to reduce wait time)
Cost of waiting, cost of service
Kendall-Lee Notation 1/2/3/4/5/6
Interarrival times iid occurrence is in in the same distribution and is independent
M = Interarrival times are independent, identically distributed (iid) (and exponentially
distributed
D= Interarrival times are iid and deterministic
Ek = Interarrival times are iid Erlangs with shape parameter k.
GI = Interarrival times are iid and governed by some other general distribution
Service times
M = Service times are iid and exponentially distributed
D = Service times are iid and deterministic
Ek = Service times are iid Erlangs with shape parameter k.
G = Service times are iid and governed by some general distribution
Number of parallel servers
Queue discipline FCFS, LCFS, SIRO, Random, Preempt/priority, Triage, SPT, EDD, LWR (least work
remaining, variant of SPT, but looks at processing time of all remaining steps), Slack (variant of
EDD, smallest difference between due date and total time remaining), Critical Ratio (time until
due date/work time remaining, if less than one you are late)
Max entities in system
Population of entities