This stock and flow diagram is an updated working draft of a conceptual model of a dune-lake system in the Northland region of New Zealand.
Clone of Stock and flow diagram of nitrogen in a lake
From science Dec 2106 article showing a CLD diagram
Lake fish regime shift
Predator-Prey Interactions (Wolf & Moose) QC
A simulation illustrating simple predator prey dynamics. You have two populations.
Clone of Predator Prey
European Masters in System Dynamics 2016
New University of Lisbon, Portugal
Simple model to represent oyster individual growth by simulating feeding and metabolism.
EMSD 2016
To calculate emission amount from mobile sources in particular from road traffic by vehicle age-cohort in DKI Jakarta - Indonesia
Vehicle Emission Amount using Age-Cohort
HANDY Model of Societal Collapse from Ecological Economics
Paper see also D Cunha's model at IM-15085
Clone of Human and Nature Dynamics of Societal Inequality
Diagrams of theories of control of destiny at multiple scales as fundamental causes of social determinants of health from Whitehead 2016 article in Health and Place
Control over decisions and health inequalities at multiple scales of experience
The following insight shows the level of crime in the town of Bourke in comparison to the levels of Police and Community Engagement
Clone of Crime vs. Engagement
The following insight shows the level of crime in the town of Bourke in comparison to the levels of Police and Community Engagement
Clone of Crime vs. Engagement
This is step 5 in making a climate model based on our insights of how trees actively contribute to the cooling capcacity of the Earth.
In the prevoious step we added the reflection of sun energy by Clouds
In this step we added aabsorption of near infrared by clouds and the biotic pump
Present the temperature of the Earth is 288 Kelvin. Without Earth would be 255 Kelvin. So the energy balance of the Earth add 33 Kelvin.
We optimize in step 4 the variable GHG-effect and the optimal number is 0,29625 in this model.
With Our-Green-Spine we have discovered new insights how trees / forest / green structures are part of the managing system of controlling the temperature of our Earth via their cooling capacity by using water and influencing the water cycle. We want to translate our insights in a climate model. People who to join us please send an email to marcel.planb@gmail.com.
Thanks, Marcel de Berg
Backup of workversion Clone of Model 6 integrating Biotic Pump
The time-variable solution to a step-function change in inflow concentration for an ideal, completely mixed lake.
Clone of Clone of Clone of ENVE 431 - HW5 - PROBLEM 7
This is step 7 based on model 5 in making a climate model based on our insights of how trees actively contribute to the cooling capcacity of the Earth.
In this step we added the PeTa-effect and the Atmosferic Window.
Present the temperature of the Earth is 288 Kelvin. Without Earth would be 255 Kelvin. So the energy balance of the Earth add 33 Kelvin.
We optimize the variable GHG-effect and the optimal number is 0.29625 in this model.
With Our-Green-Spine we have discovered new insights how trees / forest / green structures are part of the managing system of controlling the temperature of our Earth via their cooling capacity by using water and influencing the water cycle. We want to translate our insights in a climate model. People who to join us please send an email to marcel.planb@gmail.com.
Thanks, Marcel de Berg
Clone of Model 5 adding Reflection by clouds optimal GHG effect
This model is a classic simulation of the production cycle in the ocean, including the effects of the thermocline in switching off advection of dissolved nutrients and detritus to the surface layer.
It illustrates a number of interesting features including the coupling of three state variables in a closed cycle, the use of time to control the duration of advection, and the modulus function for cycling annual temperature data over multiple years.
The model state variables are expressed in nitrogen units (mg N m-3), and the calibration is based on:
Baliño, B.M. 1996. Eutrophication of the North Sea, 1980-1990: An evaluation of anthropogenic nutrient inputs using a 2D phytoplankton production model. Dr. scient. thesis, University of Bergen.
Fransz, H.G. & Verhagen, J.H.G. 1985. Modelling Research on the Production Cycle of Phytoplankton in the Southern Bight of the Northn Sea in Relation to Riverborne Nutrient Loads. Netherlands Journal of Sea Research 19 (3/4): 241-250.
This model was first implemented in PowerSim some years ago by one of my M.Sc. students, who then went on to become a Buddhist monk. Although this is a very Zen model, as far as I'm aware, the two facts are unrelated.
Clone of NPD model (Nutrients, Phytoplankton, Detritus)
jute bag project: prototype
This is a simple mass balance model simulating the lake's nutrient dynamics in Lake Tai over time and it's removal of phosphorous saturation.
Simple mass balance model for lakes, based on the Vollenweider equation:
dMw/dt = Min - sMw - Mout
Clone of Lake Taihu Model
Simple model to illustrate oyster growth based on primary production of Phytoplankton as a state variable, forced by light and nutrients, running for a yearly period.
Phytoplankton growth based on on Steele's and Michaelis-Menten equations), where:
Primary Production=(([Pmax]*[I]/[Iopt]*exp(1-[I]/[Iopt])*[S])/([Ks]+[S]))
Pmax: Maximum production (d-1)
I: Light energy at depth of interest (uE m-2 s-1)
Iopt: Light energy at which Pmax occurs (uE m-2 s-1)
S: Nutrient concentration (umol N L-1)
Ks: Half saturation constant for nutrient (umol N L-1).
Further developments:
- Nutrients as state variable in cycle with detritus from phytoplankton and oyster biomass.
- Light limited by the concentration of phytoplankton.
- Temperature effect on phytoplankton and Oyster growth.
Clone of Oyster Growth based on Phytoplankton Biomass
Fooodwaste happens everywhere and in every part
of the food cycle even if nobody wants it to happen.
We created a local solution to
reduce the waste. This solution is situated in Belgium (Kotrijk) where an
exchange system (for services) already exists and it is called letsleie http://www.letsleie.be.
We did choose letstlei because their
exchange system doesn’t work with money but with a fictive money system
"vlasbloemen". In their system we want to integrate the exchange of
food leftovers. After some years the system could become world wide.
Our solution begins with an event in a
neighbourhood or apartments. This event brings the neighbours together who
don't know each anymore. It explains the existing system and the problems of the
food waste. Every person had to take a leftover and chefs will create a
delicious meal of it. The members will receive a food box who is biodegradable
and contains a QR code that will simplify the food/ service exchange.
People will talk to each other after the event
and more and more people will join without needing new publicity.
Foodwaste Reducing by exchanging
Clone of MLP Bathtub Insight with outflow depending on water level
A model of an infectious disease and control
Clone of Disease Dynamics (Agent Based Modeling)
Modeling forest succession in a northeast deciduous forest.
Clone of Lab1 Forestry Succession Model
Fig 3.1 from Jorgen Randers book 2052 a Global Forecast for the Next Forty Years
Global 2052 Forecast
The purpose of this deer management model is to explore the capacity of wildlife management actions to help us adapt to the effects of climate change.
Story Telling - Deer Management Under Climate Change
