7-Day SELES Course Day 4

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Contents:

Spatio-temporal contexts

 * landscape change arises as the result of feedback between system state and definable processes or entities
 * as agents of landscape change, processes react to and modify the landscape state in spatio-temporal contexts
 * a spatio-temporal context is the set of information (i.e. state variables) available at a particular time and place
 * contexts provide a general hierarchical framework for describing landscape dynamics
 * SELES is a language for:
 * creating a spatio-temporal state-space
 * defining behaviours to navigate through contexts in this state-space, and
 * specifying state changes in those contexts
 * by managing contexts appropriately, models of various forms can be created, including:
 * cellular automata
 * individual-based models (IBMs)
 * spatio-temporal Markov chains

Landscape Event Properties

 * Initial State
 * Return Time
 * Event Location
 * Number of Clusters
 * Probability of Initiation
 * Transitions
 * Spread Rate
 * Spread Location
 * Probability of Spread
 * Number of Spread Recipients

Event Initiation




NUMCLUSTERS: Replacement

 * Default: without replacement
 * Option:
 * NUMCLUSTERS WITH REPLACEMENT

PROBINIT: SORTED

 * Default: probabilistic
 * Option:
 * PROBINIT ORDERED
 * Process cells in decreasing order according to value of PROBINIT

PROBINIT: RANDOM

 * Default: process from bottom left to top right or vice versa (i.e. don’t count on it)
 * Option:
 * PROBINIT RANDOM
 * Process cells in random order

PROBINIT: RECOMPUTE

 * Default: computed once at start of initiation
 * Option:
 * PROBINIT RECOMPUTE
 * Indicates that probabilities for unprocessed cells may be recomputed by a call to RECOMPUTE expression