Influence of migration on the number of working-age population.
Influence of migration on the number of working-age population.
 Acest model este adaptat după reprezentarea lui Harmut Bossel, în lucrarea  "System Zoo 3 Simulation Models, Economy, Society, Development."  Utilizarea modelului ne poate ajuta pentru a vizualiza evolutia populatiei pe grupe de varsta sau pentru a gestiona probleme cum ar fi ocuparea forței de mun
Acest model este adaptat după reprezentarea lui Harmut Bossel, în lucrarea  "System Zoo 3 Simulation Models, Economy, Society, Development."
Utilizarea modelului ne poate ajuta pentru a vizualiza evolutia populatiei pe grupe de varsta sau pentru a gestiona probleme cum ar fi ocuparea forței de muncă.
Show relation of birth and death rate over time, creating the elements of the demographic transition. This one is for Ghana. You can clone this insight for other nations, just plug in the new crude birth and death rates and find the starting population in 1960.
Show relation of birth and death rate over time, creating the elements of the demographic transition. This one is for Ghana. You can clone this insight for other nations, just plug in the new crude birth and death rates and find the starting population in 1960.
Influence of migration on the number of working-age population.
Influence of migration on the number of working-age population.
Influence of migration on the number of working-age population.
Influence of migration on the number of working-age population.
This simulation examines the caloric well of the world. World population is estimated to start at about 7.7 billion. Per capita estimates are from the International Energy Agency (IEA).
This simulation examines the caloric well of the world. World population is estimated to start at about 7.7 billion. Per capita estimates are from the International Energy Agency (IEA).
This simulation examines carbon stocks and flows as a function of population.
This simulation examines carbon stocks and flows as a function of population.
  ​Predator-prey
models are the building masses of the bio-and environments as bio
masses are become out of their asset masses. Species contend, advance and
scatter essentially to look for assets to support their battle for their very
presence. Contingent upon their particular settings of uses, they

​Predator-prey models are the building masses of the bio-and environments as bio masses are become out of their asset masses. Species contend, advance and scatter essentially to look for assets to support their battle for their very presence. Contingent upon their particular settings of uses, they can take the types of asset resource-consumer, plant-herbivore, parasite-have, tumor cells- immune structure, vulnerable irresistible collaborations, and so on. They manage the general misfortune win connections and thus may have applications outside of biological systems. At the point when focused connections are painstakingly inspected, they are regularly in actuality a few types of predator-prey communication in simulation. 

 Looking at Lotka-Volterra Model:

The well known Italian mathematician Vito Volterra proposed a differential condition model to clarify the watched increment in predator fish in the Adriatic Sea during World War I. Simultaneously in the United States, the conditions contemplated by Volterra were determined freely by Alfred Lotka (1925) to portray a theoretical synthetic response wherein the concoction fixations waver. The Lotka-Volterra model is the least complex model of predator-prey communications. It depends on direct per capita development rates, which are composed as f=b−py and g=rx−d. 

A detailed explanation of the parameters:

  • The parameter b is the development rate of species x (the prey) without communication with species y (the predators). Prey numbers are reduced by these collaborations: The per capita development rate diminishes (here directly) with expanding y, conceivably getting to be negative. 
  • The parameter p estimates the effect of predation on x˙/x. 
  • The parameter d is the death rate of species y without connection with species x. 
  • The term rx means the net rate of development of the predator population in light of the size of the prey population.

Reference:

http://www.scholarpedia.org/article/Predator-prey_model

 

 This is a basic model for use with our lab section.  The full BIDE options.

This is a basic model for use with our lab section.  The full BIDE options.

 ​Physical meaning of the equations  The Lotka–Volterra model makes a number of assumptions about the environment and evolution of the predator and prey populations:        1. The prey population finds ample food at all times.    2. The food supply of the predator population depends entirely on the
​Physical meaning of the equations
The Lotka–Volterra model makes a number of assumptions about the environment and evolution of the predator and prey populations:

1. The prey population finds ample food at all times.
2. The food supply of the predator population depends entirely on the size of the prey population.
3. The rate of change of population is proportional to its size.
4. During the process, the environment does not change in favour of one species and genetic adaptation is inconsequential.
5. Predators have limitless appetite.
As differential equations are used, the solution is deterministic and continuous. This, in turn, implies that the generations of both the predator and prey are continually overlapping.[23]

Prey
When multiplied out, the prey equation becomes
dx/dtαx - βxy
 The prey are assumed to have an unlimited food supply, and to reproduce exponentially unless subject to predation; this exponential growth is represented in the equation above by the term αx. The rate of predation upon the prey is assumed to be proportional to the rate at which the predators and the prey meet; this is represented above by βxy. If either x or y is zero then there can be no predation.

With these two terms the equation above can be interpreted as: the change in the prey's numbers is given by its own growth minus the rate at which it is preyed upon.

Predators

The predator equation becomes

dy/dt =  - 

In this equation, {\displaystyle \displaystyle \delta xy} represents the growth of the predator population. (Note the similarity to the predation rate; however, a different constant is used as the rate at which the predator population grows is not necessarily equal to the rate at which it consumes the prey). {\displaystyle \displaystyle \gamma y} represents the loss rate of the predators due to either natural death or emigration; it leads to an exponential decay in the absence of prey.

Hence the equation expresses the change in the predator population as growth fueled by the food supply, minus natural death.


The poverty cycle.  My friend gave me the topic "poverty" and so I made this.
The poverty cycle.  My friend gave me the topic "poverty" and so I made this.
Influence of migration on the number of working-age population.
Influence of migration on the number of working-age population.
Influence of migration on the number of working-age population.
Influence of migration on the number of working-age population.
 This is a basic BIDE (birth, immigration, death, emigration) model.  Not all parts are implemented, however Birth and Death are.

This is a basic BIDE (birth, immigration, death, emigration) model.  Not all parts are implemented, however Birth and Death are.

Adding change over time to relative risk, odds ratio and population attributable fraction epidemiology concepts see  wikipedia  and  examples  . Could also add deaths and competing risks
Adding change over time to relative risk, odds ratio and population attributable fraction epidemiology concepts see wikipedia and examples .
Could also add deaths and competing risks