Based on model discussed by John D. Sterman (p 508) in All models are wrong: reflections on becoming a systems scientist (2002). Task: (A) Sketch what you think the resultant graph will be (see directions for drawing in model). (B) Then Run Simulation. Optional Extension: Replace Graph In/Out Flow connection with a connection from Trig. function. Repeat (A) & (B).
Based on model discussed by John D. Sterman (p 508) in All models are wrong: reflections on becoming a systems scientist (2002). Task: (A) Sketch what you think the resultant graph will be (see directions for drawing in model). (B) Then Run Simulation. Optional Extension: Replace Graph In/Out Flow connection with a connection from Trig. function. Repeat (A) & (B).
Based on model discussed by John D. Sterman (p 508) in All models are wrong: reflections on becoming a systems scientist (2002). Task: (A) Sketch what you think the resultant graph will be (see directions for drawing in model). (B) Then Run Simulation. Optional Extension: Replace Graph In/Out Flow connection with a connection from Trig. function. Repeat (A) & (B).
Based on model discussed by John D. Sterman (p 508) in All models are wrong: reflections on becoming a systems scientist (2002). Task: (A) Sketch what you think the resultant graph will be (see directions for drawing in model). (B) Then Run Simulation. Optional Extension: Replace Graph In/Out Flow connection with a connection from Trig. function. Repeat (A) & (B).
A Conveyor is essentially an infinite order exponential delay. This insight illustrates how increasing the order of an exponential delay begins to approximate a conveyor. The 10th order delay very closely aligns to the Delay 10 Conveyor.
A model which simulates the competition between logging versus adventure tourism (mountain bike ridding) in Derby Tasmania. Simulation borrowed from the Easter Island simulation.
How the model works.
Trees grow, we cut them down because of demand for Timber amd sell the logs.
With mountain bkie visits. This depends on past experience and recommendations. Past experience and recommendations depends on Scenery number of trees compared to visitor and Adventure number of trees and users. Park capacity limits the number of users.
Interesting insights
It seems that high logging does not deter mountain biking. By reducing park capacity, visitor experience and numbers are improved. A major problem is that any success with the mountain bike park leads to an explosion in visitor numbers. Also a high price of timber is needed to balance popularity of the park. It seems also that only a narrow corridor is needed for mountain biking
This model which simulates the competition of Logging with Mountain Tourism in Derby, Tasmania. This main reason of this simulation is to find if logging will affect the mountain tourism and by any chance they can co-exist.
How the model works.
Both Timber harvesting and mountain tourism can bring the economic contribution to Tasmania. In the Logging industry, it helps increase the need of employment and at the same time logging generate the profit through selling those timbers. In the Mountain Tourism industry, it can get the revenue through couple of ways which include accommodation (approximately 3 days find in paper), Restaurant and parking fee. However, the low growth rate of the trees is not keeping up with the rate of logging, if the trees getting less in Derby mountain, it will affect the sights and the riding experience for tourists, which will affect the satisfaction and expectation as it depends on the sights and experience. The satisfaction and expectation will influence the number of visitors, if they satisfied, they can come again or tell others about the great experience, if not, more and more people will not come again.
Interesting insights
It seems like logging has no significant negative effect to the mountain tourism, compare the forestry income with the tourism income, tourism income gradually higher than the forestry income at last, which means tourism is in a very important position, as long as the visitors are stable, tourism industry can provide greater economic contribution, stakeholders and governments can find the balance by maintain the status or better slightly reduce logging in order to make them co-exist.
Based on model discussed by John D. Sterman (p 508) in All models are wrong: reflections on becoming a systems scientist (2002). Task: (A) Sketch what you think the resultant graph will be (see directions for drawing in model). (B) Then Run Simulation. Optional Extension: Replace Graph In/Out Flow connection with a connection from Trig. function. Repeat (A) & (B).
Modelo baseado na Figura 1 do paper "Forecasting the need for medical specialists in Spain: application of a system dynamics model" (*) de Patricia Barber (**), Beatriz González López-Valcárcel.
Based on model discussed by John D. Sterman (p 508) in All models are wrong: reflections on becoming a systems scientist (2002). Task: (A) Sketch what you think the resultant graph will be (see directions for drawing in model). (B) Then Run Simulation. Optional Extension: Replace Graph In/Out Flow connection with a connection from Trig. function. Repeat (A) & (B).
Based on model discussed by John D. Sterman (p 508) in All models are wrong: reflections on becoming a systems scientist (2002). Task: (A) Sketch what you think the resultant graph will be (see directions for drawing in model). (B) Then Run Simulation. Optional Extension: Replace Graph In/Out Flow connection with a connection from Trig. function. Repeat (A) & (B).
Based on model discussed by John D. Sterman (p 508) in All models are wrong: reflections on becoming a systems scientist (2002). Task: (A) Sketch what you think the resultant graph will be (see directions for drawing in model). (B) Then Run Simulation. Optional Extension: Replace Graph In/Out Flow connection with a connection from Trig. function. Repeat (A) & (B).
A pest known as a grape-leaf hopper can cause considerable losses in vineyards. Periodically it was found that a natural parasite, anagrus epos, drastically reduced the size of the hopper population. This, in turn, led to a reduction in food (hoppers) available to the parasite and the parasite population declined until the hopper population increased again. This cycle would repeat.It was found that the parasite, anagrus epos, also feeds on a non-pest leaf hopper which feeds on blackberries. By planting small patches of wild blackberries in the vineyards, the growers were able to maintain a stable parasite population that was large enough to control population explosions of both leaf hoppers.
A body is thrown obliquely into the vacuum at an initial velocity of 100 m / s, in a direction that forms with the horizontal an angle x, such that sin (x) = 0.8 and cos (x) = 0.6. Adopting g = 10m / s², determine:
(a) the horizontal and vertical velocity component modules at the moment of launch;
(b) the instant at which the body reaches the highest point of its trajectory;
c) the maximum height reached by the body;
d) The range of the throw.
Source: RAMALHO, NICOLAU AND TOLEDO; Fundamentos de Física, Volume 1, 8th edition, pp. 12 - 169, 2003.
This model may be cloned and modified without prior permission of the authors. Thanks for quoting the source.
