Courses/CS 461/Winter 2006/Justin Padilla/Week 2

From CSWiki

[edit] Model: Wolf-Sheep Predation

Emergent Phenomena:

• Sheep overrun wolves
• Wolves overrun sheep, then die off

Rules of the Agents:

• If no grass, sheep simply live until they are eaten
• If grass, sheep live as long as their energy lasts
• Wolves live as long as their energy lasts
• Wolves get energy from sheep, sheep from grass

Why the Emergence?:

• Sheep overrun wolves most often because their population either begins at, or is reduced by consumption to, so low that wolves run out of energy and die before they can eat another sheep, then the sheep reproduce unhindered by wolves.
• Wolves overrun sheep when the population of sheep is large enough for wolves to eat and reproduce rapidly, then they consume the remainder of sheep and are left to starve, eventually dying completely.

[edit] Model: Traffic Basic

Emergent Phenomena:

• Cars eventually stop colliding and all go the same speed.

Rules of the Agents:

• Cars slow to the speed of the car they reach in front of them minus the slow speed.
• Cars accelerate at the speed-up rate.

Why the Emergence:

• If the slow speed is very low or zero, the cars will eventually find equilibrium and reach the maximum speed, with no further collisions. This is because they slow very little in comparison to the car in front of them, and then accelerate again, making collisions with the car behind them less likely. This likelihood is then propogated down the line until eventually there are no further collisions, and no further slowing.

[edit] Model: Life

Emergent Phenomena:

• Moving patterns

Stage 1
X  
X X
XX 

Stage 2
  X
XX
 XX

Stage 3
 X
X    (Rotation of stage 1)
XXX

Stage 4
X X
XX   (Rotation of stage 2)
 X

• Infinite looping patterns

Stage 1
XXX

Stage 2
X
X
X

• Stable patterns

 XX
X  X
X  X
 XX

 X
X X
 X

 XX
X  X
 XX

Rules of the Agents:

• Check all 8 neighboring cells
• if 3 alive, dead cell comes alive
• if 2 alive, cell remains in its state(alive or dead)
• if more than 3, or less than 2, live cell dies

Why the Emergence:

• I have observed one type of moving pattern, which resembles an arrow or an "L" with an apostrophe. This pattern goes through 4 stages, each adjusting the cells within it and the cells around it that after 4 changes it emerges again one cell to the west, and one cell to the south. Mirrors of this shape have mirrors of its movements.
• 3 cells in a row/column: center cell has 2 live neighbors and remains alive, 2 perpendicular dead cells have 3 live neighbors and become alive, 2 live neighbors only have 1 live neighbor and die. This pattern will loop from a column to a row indefinitely.
• All cells have 2 living neighbors: live cells never die, dead cells never come alive.