Lab 6 – Final assessment
Task 1
For this final task in Vensim, let your final model run from 1900 until 2100 in one year steps on the Euler
algorithm.
First, create a simple stock and flow model that keeps track of the amount of rock at three different
altitudes (high, mid & low altitude) on a small mountain’s moraine, where rock has the ability to move
downhill either through ‘frost bursting’ (high to mid altitude) or through ‘deterioration from other forms
of weathering’ (mid to low altitude). There are estimates on the amount of rock at the different altitude:
– high: 500,000 t
– mid: 1,000,000 t
– low: 2,000,000 t
Furthermore, the amount of rock lost from high altitudes to mid altitudes annually is estimated to range
between 800 and 1,200 t.
Extend your model
Scientists have been monitoring the annual loss of rock from mid altitudes as well as the amount of rock
arriving at low altitude. They did so, by color marking and measuring rocks within the perimeter of a
research station at mid altitude and measuring the colored rocks arriving in the perimeter of a research
station at low altitude.
Their measurements show that the annual loss from mid altitude (2,000 t) does not completely reach the
lower research station in the same year. Due to the color markings, they can determine that from the
annual loss in mid altitude only 250 t arrive at low altitude in the same year (i.e. the same time step). They
reason, that it takes the rock more than one year to reach the lower research station due to the long
distance between the stations. Furthermore, they also see rock arriving at low altitude that was lost from
mid altitudes in prior years. They know this as they use different color markings for the rock for different
years and each year they have a collection of rocks with different color markings in the perimeter of their
research station at low altitude. Finally, they find out that the loss from one year (2,000 t) arrives at low
altitude in a linear fashion.
Run your final model that incorporates all the above-mentioned information and provide a screenshot of
the model, a table that shows the equations of all your stocks, flows and auxiliary variables as well as a
graph that shows the development of the 3 stocks over time!
Task 2
The following stock and flow model shows the interlinked relationships between foxes, rabbits, park
visitors and leftovers (edible waste left by park visitors) in a simplified way. However, there are a few
mismatches between the model and accompanying equations below the model.
(1) ∆𝐹𝐹
∆𝑡𝑡 = 𝑎𝑎1𝐹𝐹 𝑅𝑅 𝑎𝑎5𝐿𝐿𝐿𝐿 − 𝑏𝑏1𝐹𝐹 𝑃𝑃𝑃𝑃
(2) ∆𝑅𝑅
∆𝑡𝑡 = 𝑎𝑎2𝑅𝑅 − 𝑏𝑏2𝑅𝑅 𝐹𝐹 𝑃𝑃𝑃𝑃
(3) ∆𝑃𝑃𝑃𝑃
∆𝑡𝑡 = 𝑎𝑎3𝑃𝑃𝑃𝑃 𝐹𝐹 𝑅𝑅 − 𝑏𝑏3𝑃𝑃𝑃𝑃 𝐿𝐿𝐿𝐿
(4) ∆𝐿𝐿𝐿𝐿
∆𝑡𝑡 = a4PV – b4F
For the report:
• What are these mismatches?
• Specify for each mismatch, which version (either the process in the diagram or its representation
in the equation) makes more sense to you and why?
• Present your answers in the report as follows:
o Mismatch 1: In the formula X is missing, but it occurs in the diagram. I think, it should be
in the formula as well, because…. Logical/ecological/model structure related answer
(whichever you think fits bests); you could also argue for both ways if you find arguments
for both sides
The deadline for this report is 29.7.2022 23:59 sharp!
Foxes F
Rabbits R
Park visitor PV
Leftovers LO
Interaction terms a1, a2, a3, a4, a5,
b1, b2, b3, b4, b5
Time t
NUR2115 ATI System Disorder
ACTIVE LEARNING TEMPLATES System Disorder STUDENT NAME _____________________________________ DISORDER/DISEASE PROCESS __________________________________________________________ REVIEW MODULE CHAPTER___________ ACTIVE LEARNING TEMPLATE: ASSESSMENT SAFETY CONSIDERATIONS PATIENT-CENTERED CARE Alterations in Health (Diagnosis) Pathophysiology Related to Client Problem Health Promotion and Disease Prevention Risk Factors Expected Findings Laboratory Tests Diagnostic Procedures Complications Therapeutic Procedures Interprofessional Care Nursing Care Medications Client Education
