This
paper aims at describing a case where system dynamics modeling was used to evaluate
the effects of information and material supply lead-time variation on sales
contributions margins and operating cash conversion cycle of a commodity export
business. An empirical dynamic model,
loaded with econometric theory of price effect on competitive demand, was used
to describe the input data. The model simulation
outputs proved themselves relevant in analyzing the complex interconnections of
multiple variables affecting the
profitability in a commercial routine, supporting the decision process among
sales managers.
A framework exploring flood risk management in a developing city, under
the new paradigm of coexist - characterised by broader, system-wide goals, a recognition of the role played and benefits provided by flood processes, and higher levels of flood risk awareness.
People, generally, do not seem to be conscious of, or care
about, the enormous dangers of climate change and even the possibility of a
devastating war in the Korean peninsula that could turn nuclear. They carry on
with their routine and banal conversations as if that was all that mattered. In
the 60s there were peace demonstration, there was more awareness and public engagement
in the face of the thread of nuclear war. Could the pressures and demands of modern
capitalism, now no longer tamed by a competing communist system that could potentially
appear to be more attractive, be a causal factor? People caught up in the turmoil of a positive
feedback loop rarely perceive reality beyond it. This simple CLD tries to
illustrate the dynamic and feedback loops that could be responsible for this strange
apathy and how our present day economic system could be blinding us to imminent
danger.
This model illustrates a scenario whereby a client wanted to move from a Fixed rate/ton/route transported to a Tendered rate/ton/route in order to reduce the overall cost of transport. There have been considerable ''unintended consequences'' as a result of this.
Simple model of the global economy, the global carbon cycle, and planetary energy balance.
The planetary energy balance model is a two-box model, with shallow and deep ocean heat reservoirs. The carbon cycle model is a 4-box model, with the atmosphere, shallow ocean, deep ocean, and terrestrial carbon.
The economic model is based on the Kaya identity, which decomposes CO2 emissions into population, GDP/capita, energy intensity of GDP, and carbon intensity of energy. It allows for temperature-related climate damages to both GDP and the growth rate of GDP.
This model was originally created by Bob Kopp (Rutgers University) in support of the SESYNC Climate Learning Project.
Simple model of the global economy, the global carbon cycle, and planetary energy balance.
The planetary energy balance model is a two-box model, with shallow and deep ocean heat reservoirs. The carbon cycle model is a 4-box model, with the atmosphere, shallow ocean, deep ocean, and terrestrial carbon.
The economic model is based on the Kaya identity, which decomposes CO2 emissions into population, GDP/capita, energy intensity of GDP, and carbon intensity of energy. It allows for temperature-related climate damages to both GDP and the growth rate of GDP.
This model was originally created by Bob Kopp (Rutgers University) in support of the SESYNC Climate Learning Project.
Clusters of interacting methods for improving health services network design and delivery. Includes Forrester quotes on statistical vs SD methods and the Modeller's dilemma. Simplified version of IM-14982 combined with IM-17598 and IM-9773
In CIV4 a City's Health stock is a flourishing yet complex condition which acts as a City attribute intended to limit growth. Positive and negative feedback impacts City Health flow and derives from many sources: city's site, buildings, wonders, civics, resources, population, etc.
What drives this flow? When a cities unhealthiness is greater than its health limit, then for each point of population above the health limit consumes 3 food apiece rather than the standard 2 pieces. This further depletes city resources leading to starvation. In addition the city’s health also affects the rate at which it accumulates food.
For example: too much growth causes overpopulation which leads to an unhealthy city. This unhealthy city leads to less food accumulation thereby resulting in starvation which further compounds the cities unhealthiness.
Goodwin cycle IM-2010 with debt and taxes added, modified from Steve Keen's illustration of Hyman Minsky's Financial Instability Hypothesis "stability begets instability". This can be extended by adding the Ponzi effect of borrowing for speculative investment.
