NetLogo User Community Models
by Christos Tzivanakis (Submitted: 05/28/2013)
WHAT IS IT?
This model simulates the garbage collection operations in part of a city grid.
HOW IT WORKS
BINS (agents) situated in the corners of blocks of a city (patches) are receiving waste units from local residents. The load increase step and the maximum capacity of the bins can be modified. Bin content increases randomly in a range defined by the load increase step on a hourly basis. When a bin reaches (and slightly exceeds) its capacity, it turns black and stops receiving more waste.
Garbage collection is undertaken by two different fleets of GARBAGE TRUCKS (breeds of agents). All trucks move around across the city road network with a speed of 1 road-patch/minute and have a maximum load capacity according to their type. PUBLIC (red) trucks' operation cost is defined on a time basis while PRIVATE (blue) trucks' operation cost is proportional to the collected waste units.
As soon as a garbage truck is full, its color turns black and is "teleported" to the north-eastern point of the city (yellow patch), where it dumps its waste. All empty garbage trucks return to duty.
HOW TO USE IT
Before starting the execution of the model the user should define the dimensions of the city and the bins' and garbage trucks' parameters.
During runtime, the tools for assessing the operation are graphs showing the cost of garbage collection and the volume of collected waste per type of truck as well as how many waste units are currently still inside the bins across the whole city on a hourly basis.
A text output area is refreshed on a daily basis in order to provide the values of certain key performance indices such as "Cost per waste unit collected" and "Percentage of waste units (inside bins)/(bins+trucks)".
THINGS TO NOTICE
Changing the speed slider to a slower setting can give a sense of detail, while setting it to a faster speed one can quickly advance days of operation.
When the garbage trucks start to fall behind with waste collection bins situated far from the garbage depot (yellow patch) are the first ones to reach their maximum capacity due to their greater distance.
THINGS TO TRY
The efficiency of the operation is positively influenced by increasing the number of the trucks and their capacity, however this can seriously increase the cost if not done cautiously.
EXTENDING THE MODEL
One extra feature would be the flexibility to place the bins in spots other than block corners. Also, a new population (breed) of bins can be added that would collect the recycling waste, which should be assigned to a third fleet(breed) of garabge trucks specialized for this type of waste. Finally, it would be more realistic if garbage trucks could drive back to empty their content, instead of being instantly teleported.
No particularly interesting features of NetLogo were used.
The movement of the truck-agents is largely based on the cars of the "Traffic Grid" model from the Models Library.
CREDITS AND REFERENCES
This model has been developed by Christos Tzivanakis (2012) a student in the Department of Information Technology of A.?.?.?. of Thessaloniki (Greece) as part of his undergraduate thesis on "Intelligent Agent Applications" under the supervision of Dr. Demosthenes Stamatis.
(back to the NetLogo User Community Models)