It is sometimes the case that the flow into a stock is not dependent on the amount of stuff stored in that stock.  A bathtub is often used as an example.  Think of the water stored in the bathtub as a stock.   Turn the spigot on and walk away and the flow into the bathtub is not determined by the stock.  The same is true for river flow into Lake Erie -- the rivers have no capacity to adjust flow based on how much water is already in the Lake.  Of course in both cases the stock has the capacity to overflow if teh stock exceeds some maximum capacity -- over the sides of tub or down Niagara Falls.

Here we model the population of Algeria given data between 1960 and 2013 from Worldbank.org. We used the crude birth rate and crude death rate for every 5 years since 1960 to 2005, and the rates every year from 2005 to 2013. To forecast, we used the slope of the net birth rate to calculate when the net birth rate would be zero, and used this year for our birth and death rates to are equal to zero. We assumed no net movement of people into or out of Algeria. We add that at any given time, our knowledge of the birth and death rates is not accurate, where our rates vary with a standard deviation equal to the standard deviation in the rates from 1960 to 2013.

Simple model to illustrate   algal  ,   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.

  Biogas, model  as well birefineray option to seperate c02 , chp from bogas model are proposed

Model of growth from diffusion from John Morecroft's Strategic Modelling and Business Dynamics Book Ch6 p174-191. A discussion of a bigger model of People's Express is in http://bit.ly/HdaGy4 for a related You Tube video by John Morecroft on Reflections on System Dynamics and Strategy

Births add people to a population

Growth Rate

Here we model the population of France given data between 1960 and 2013 from Worldbank.org. We used the crude birth rate and crude death rate for every 5 years since 1960 to 2005, and the rates every year from 2005 to 2013. To forecast, we used the slope of the net birth rate to calculate when the net birth rate would be zero, and used this year for our birth and death rates to are equal to zero.  We assumed no net movement of people into or out of France. We add that at any given time, our knowledge of the birth and death rates is not accurate, where our rates vary with a standard deviation equal to the standard deviation in the rates from 1960 to 2013

Model of growth from diffusion from John Morecroft's Strategic Modelling and Business Dynamics Book Ch6 p174-191. A discussion of a bigger model of People's Express is in http://bit.ly/HdaGy4 for a related You Tube video by John Morecroft on Reflections on System Dynamics and Strategy

OVERSHOOT GROWTH GOES INTO TURBULENT CHAOTIC DESTRUCTION

The existing global capitalistic growth paradigm is totally flawed

The chaotic turbulence is the result of the concept of infinite bigness this has been the destructive influence on all empires and now shown up by Feigenbaum numbers and Dunbar numbers for neural netwoirks

See Guy Lakeman Bubble Theory for more details on keeping systems within finite limited size working capacity containers (villages communities)

For at least some period of time there are many situations in which the growth of a population (or some other type of stock) is directly proportional to the size of the stock.  For example, the initial rate of growth when an invasive species is introduced, money in the bank given a fixed interest rate and no withdrawals, etc.  If material or energy are in any way necessary, unconstrained growth eventually must become constrained.

Here we model the population of France given data between 1960 and 2013 from Worldbank.org. We used the crude birth rate and crude death rate for every 5 years since 1960 to 2005, and the rates every year from 2005 to 2013. To forecast, we used the slope of the net birth rate to calculate when the net birth rate would be zero, and used this year for our birth and death rates to are equal to zero.  We assumed no net movement of people into or out of France. We add that at any given time, our knowledge of the birth and death rates is not accurate, where our rates vary with a standard deviation equal to the standard deviation in the rates from 1960 to 2013

Here we model the population of France given data between 1960 and 2013 from Worldbank.org. We used the crude birth rate and crude death rate for every 5 years since 1960 to 2005, and the rates every year from 2005 to 2013. To forecast, we used the slope of the net birth rate to calculate when the net birth rate would be zero, and used this year for our birth and death rates to are equal to zero.  We assumed no net movement of people into or out of France. We add that at any given time, our knowledge of the birth and death rates is not accurate, where our rates vary with a standard deviation equal to the standard deviation in the rates from 1960 to 2013

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.

the simulation shows how our money grows overtime as we keep investing our money every month in money market mutual funds. But overtime monetary value keeps growing up with constant rate of 3%, so what this simulation shows us is the real value of the money we invest in mutual funds that have a certain rate of interest.

Here we model the population of France given data between 1960 and 2013 from Worldbank.org. We used the crude birth rate and crude death rate for every 5 years since 1960 to 2005, and the rates every year from 2005 to 2013. To forecast, we used the slope of the net birth rate to calculate when the net birth rate would be zero, and used this year for our birth and death rates to are equal to zero. We assumed no net movement of people into or out of France.

This a simple and "totally accurate" model of the exponential human population.

faktor-faktor yang mempengaruhi pertumbuhan udang vannamei

Model of growth from diffusion from John Morecroft's Strategic Modelling and Business Dynamics Book Ch6 p174-191. A discussion of a bigger model of People's Express is in http://bit.ly/HdaGy4 for a related You Tube video by John Morecroft on Reflections on System Dynamics and Strategy

An ultra simplified version of LTG world3. in the end it looks like a predator/prey system

This model shows an exponential growing population

This a simple and "totally accurate" model of the exponential human population.