DRAFT conceptual model of climate change connections in Yamuna river project.
DRAFT conceptual model of climate change connections in Yamuna river project.
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Interactions between wolves and livestock depending on abundance
Interactions between wolves and livestock depending on abundance
 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.

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.

To calculate the emission from mobile sources (road traffic) in DKI Jakarta, Indonesia
To calculate the emission from mobile sources (road traffic) in DKI Jakarta, Indonesia
A single resource is used​ with a constant rate and converted into products in use. After a while, these products become unusable because of aging. The recycling of these unusable products is imperfect, thus the amount of not recyclable resource grows (until a better recycling process is invented).
A single resource is used​ with a constant rate and converted into products in use. After a while, these products become unusable because of aging. The recycling of these unusable products is imperfect, thus the amount of not recyclable resource grows (until a better recycling process is invented).
Clone of Pesticide Use in Central America for Lab work        This model is an attempt to simulate what is commonly referred to as the “pesticide treadmill” in agriculture and how it played out in the cotton industry in Central America after the Second World War until around the 1990s.     The cotto
Clone of Pesticide Use in Central America for Lab work


This model is an attempt to simulate what is commonly referred to as the “pesticide treadmill” in agriculture and how it played out in the cotton industry in Central America after the Second World War until around the 1990s.

The cotton industry expanded dramatically in Central America after WW2, increasing from 20,000 hectares to 463,000 in the late 1970s. This expansion was accompanied by a huge increase in industrial pesticide application which would eventually become the downfall of the industry.

The primary pest for cotton production, bol weevil, became increasingly resistant to chemical pesticides as they were applied each year. The application of pesticides also caused new pests to appear, such as leafworms, cotton aphids and whitefly, which in turn further fuelled increased application of pesticides. 

The treadmill resulted in massive increases in pesticide applications: in the early years they were only applied a few times per season, but this application rose to up to 40 applications per season by the 1970s; accounting for over 50% of the costs of production in some regions. 

The skyrocketing costs associated with increasing pesticide use were one of the key factors that led to the dramatic decline of the cotton industry in Central America: decreasing from its peak in the 1970s to less than 100,000 hectares in the 1990s. “In its wake, economic ruin and environmental devastation were left” as once thriving towns became ghost towns, and once fertile soils were wasted, eroded and abandoned (Lappe, 1998). 

Sources: Douglas L. Murray (1994), Cultivating Crisis: The Human Cost of Pesticides in Latin America, pp35-41; Francis Moore Lappe et al (1998), World Hunger: 12 Myths, 2nd Edition, pp54-55.

This diagram provides a stylised description of important feedbacks within a shallow-lake system.
This diagram provides a stylised description of important feedbacks within a shallow-lake system.

Concepts are designed for Universatility and local variables without forcing a one size fits all model.    Measurements in the course are designed to maintain a system perspective in all planning and measurement systems.       Students will acquire hands on modeling skills using either video learnin
Concepts are designed for Universatility and local variables without forcing a one size fits all model. 

Measurements in the course are designed to maintain a system perspective in all planning and measurement systems. 

Students will acquire hands on modeling skills using either video learning offered by System Thinking World host and easily viewed through the right hand side of the page conveniently located are links to the video series.  

A facilitator may offer traditional instruction or ideally students from the graduating students are teaching the next group of students and improving the way the materials is presented.

 This stock and flow diagram is a working draft of a conceptual model of a dune-lake system in the Northland region of New Zealand.

This stock and flow diagram is a working draft of a conceptual model of a dune-lake system in the Northland region of New Zealand.

This is a causal diagram story I made as an introduction to a workshop on systems thinking.
This is a causal diagram story I made as an introduction to a workshop on systems thinking.
  The effect of phosphorus on an ecosystem
 The effect of phosphorus on an ecosystem
How the 4-H club became a marketing thingy for DuPont
How the 4-H club became a marketing thingy for DuPont
This diagram describes the key processes that influence the water quality within a Northland lake.
This diagram describes the key processes that influence the water quality within a Northland lake.
This model describes the flow of energy from generation to consumption for neighborhoods in the metro Atlanta area. It also calculates the cost of energy production and the number of years it will take to recover that cost.
This model describes the flow of energy from generation to consumption for neighborhoods in the metro Atlanta area. It also calculates the cost of energy production and the number of years it will take to recover that cost.
 A simulation illustrating how the size of a fish population affects the number of fish caught and vice versa.

A simulation illustrating how the size of a fish population affects the number of fish caught and vice versa.

This is an edited copy of the original simple building heat flow. I addressed the insulation aspect of this problem by reducing the conductivity values of both the walls and windows. To address a chiller system, I integrated mechanical cooling into the process. To address solar panels, I calculated
This is an edited copy of the original simple building heat flow. I addressed the insulation aspect of this problem by reducing the conductivity values of both the walls and windows. To address a chiller system, I integrated mechanical cooling into the process. To address solar panels, I calculated the effect they may have on electricity prices by adding Solar Panel variables to the equation.