Modeling the Effects of Disasters on a Human Population and Resources Population and Resources TJHSST Computer Systems Tech Lab Joshua Yoon

Recently over the past decades, numerous disasters such as the earthquakes and tsunamis have struck all over the world This project is an attempt to not only model the effects of these disasters on a human population accurately, but also be able to extrapolate the effects of future disasters on a nearby human population using a System Dynamics approach.Abstract

System Dynamics portion of the NetLogo language, and the System Dynamics approach looks into the relationships between different local variables Difference between System Dynamics and agent-based modeling: System Dynamics looks into the relationship between variables and how these variables affect each other over time, whereas in agent- based, interactions between individuals of a population are generated randomly Background

Current System Dynamics modeler used is "Stella" Currently using NetLogo, must draw up the separate variables and the relationships between them System Dynamics can be used in many different ways, but mainly to simulate efficiency Train System Efficiency Policy on flood prevention Background cont.

Create a human population that behaves like a human population Implement a resource class, which inhibits unlimited growth of the population Implement disasters so that human population drops and recovers over time Compare simulation test results with results from actual disasters Methodology/Procedure

Disaster Class: This portion of the code handles everything there is to handle about disasters. The death rates are made by the different converters (blue diamonds), and each death rate is set to a constant. The DisasterProbability converter handles the frequency of a disaster. The converter creates a random integer from 0 to 400 and if that random integer is equal to 1, then the disaster(s) is turned on. The ActiveDisaster converter calculates new death rates if more than one disaster is turned on at once. All of these converters connect to DeathDRate, which is the final death rate due to disaster after all the disaster related death rates have been accounted for. 3 Main Components: Part 1

Resource Class: This is another stock called resources. This stock represents the resources, which are available to the population and this in turn keeps the population in check. I made this class originally to create a carrying capacity, but now I'm implementing it so that resources can also be affects by disasters. The DeathNDRate stock stands for the non-disaster death rate, and basically it is controlled by the resources and how abundant the resources are compared to the size of the population. 3 Main Components: Part 2

Human Class: This diagram controls the actual human population signified by the stock (tan box). There is an inflow (gray arrows going into stock) of people, which are new people added to the already existing population, and then there is the outflow (gray arrow going out of stock) which signifies the death of individuals in the population. The inflows are controlled by converters such as BirthRate and NewPeopleInfluxRate, whereas the outflow is controlled by the DeathDRate and DeathNDRate. 3 Main Components: Part 3

The Complete Web: 3 Main Components: Pieced Together

Simulations are now running, even though the behavior of human population hasn't been perfected. There is obviously a relationship between the variables, but that too must be perfected. Results & Conclusions

Curve looks similar to a regular human population curve, and the recovery curve is sporadic, but it exists. Must work more to fix the glitches, and then comparisons to real disaster data will begin Results & Conclusions cont.