Transcript Queueing and Hand Simulation (Project 03)

Queueing and Hand
Simulation
(Project 03)
Queueing Models
• Probabilistic and stochastic models
• Important aspects:
– Interarrival time
– Service time
– Waiting time
• Mathematics not reality!
• Several assumptions:
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Arrival process, service process
Queue size and discipline
Time horizon
Calling population
Queueing Models
• Use theoretical model to estimate the behavior of
a real system (this is only an approximation!)
• Queues are a model archetype
• Queue system entities:
– Flow unit
– Queue
– Server
• Where each entity has its own state space and
transitions
Time-Flow Mechanism
• Time-step incrementation
– Stepping through time in equal (e.g. 1 hour)
increment
Time-Flow Mechanism
• Event-step incrementation
– Calls for a simulation to proceed from one event to the
next
– Incremental time steps are uneven
– Simulation begins at time zero
– Occurrence times of the events resulting from the
simulated performance of all system components are
determined
– Master clock is updated to the time of the earliest
event occurrence
– Commonly used
Group Project
This project deals with modeling a
simple, real-world queueing system
You may work in groups of three
students (in one group: max 1
female and 1 international student)
Goal: analyze a real-world queueing
system
Group Project
Choose a small interesting system to study
Schedule a variety times to go to the site
and collect data (i.e. different hours of the
day, different days of the week)
Obtain permission from the manager of
the site
Minimum two 30-minute data-gathering
sessions on different days (the more the
better)
Group Project
Figure out what you want to analyze
Figure out what data you’ll need to collect
Analyze the data
Next week:
A 3-5 pages single-spaced nice, clean,
interesting write-up due
Present it in front of the class (15-20 minutes)