CS 420/594 — Biologically Inspired Computation
NetLogo Simulation

EM Phase-Plane

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view/download model file: EM-Phase-Plane.nlogo

WHAT IS IT?

Documentation will come later!!

This section could give a general understanding of what the model is trying to show or explain.

HOW IT WORKS

This section could explain what rules the agents use to create the overall behavior of the model.

HOW TO USE IT

This section could explain how to use the model, including a description of each of the items in the interface tab.

Epsilon controls the speed of the dynamics without changing the nullclines. Do you see why?

THINGS TO NOTICE

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THINGS TO TRY

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Begin with function G-II, which gives a Type II model. Start with Default parameters, including B = 0, and you will see the state go to the fixed point where the nullclines cross. (The calculated fixed point is u = -1.5, w = -0.3. How do your observations compare?) Rerun with greater values of B. For B > 1.24 you should see oscillatory behavior. Try several B values in the range [1.24, 1.56] and estimate the oscillation frequency for each. What happens for B > 1.57? Can you explain the significance of the B values 1.24 and 1.57 in terms of the shape of the u-nullcline where the w-nullcline crosses it?

Now try function G-I, which gives a type I model, and start again with the Default parameters. Once again it should exhibit fixed point behavior, and as you increase B you should find a threshold for oscillatory behavior at about B = 1.11. Estimate the frequency at several B values less than 1.57. Observe how Type I behavior differs from Type II. For B > 1.57 you will have fixed point behavior again; try to explain the thresholds by observing the nullclines for various B values.

EXTENDING THE MODEL

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NETLOGO FEATURES

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RELATED MODELS

This section could give the names of models in the NetLogo Models Library or elsewhere which are of related interest.

CREDITS AND REFERENCES

To refer to this model in academic publications, please use: MacLennan, B.J. (2008). NetLogo EM-Phase-Plane model. http://www.cs.utk.edu/~mclennan. Dept. of Electrical Engineering & Computer Science, Univ. of Tennessee, Knoxville.

In other publications, please use: Copyright 2008 Bruce MacLennan. All rights reserved. See http://www.cs.utk.edu/~mclennan/420/NetLogo/EM-Phase-Plane.html for terms of use.