Featured Author

John Hayward

I am a Visiting Research Fellow in Mathematics at the University of South Wales. Before my retirement, I was a senior lecturer at the university, teaching specialist courses in system dynamics, mathematical modelling and agent-based methods. I was awarded a BSc in astrophysics, and a PhD in applied mathematics, from the University of London, and then spent my career as a lecturer in mathematics. My research is in mathematical sociology with applications to the spread of social phenomena, such as ... Read more

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#1

Lactase Enzyme Simulation with Data Analysis

sim3232443 runs
383060
#2

Information Processing and Neurophysiology Model

The main dependent variable measured in the model is the membrane potential (millivolts) of two diff ... Read more
The main dependent variable measured in the model is the membrane potential (millivolts) of two different neurons in a series. You will be able to add excitatory and inhibitory neurotransmitters, and compare how these modulate electrical impulses of the two neurons. Additionally, you will be able to compare the effects of three neurotoxins: Tetrodotoxin, botulinum toxin, and sarin nerve gas. While extremely lethal, these toxins are very instructive in understanding neurons because of the specific way the toxins act. Each toxin modifies or inhibits a specific molecule in neurons that help process and transmit information.
sim84021 runs
infromation processing neurophysiology biology
115407
#3

COVID-19 Simulator

This simulator looks at the spread of COVID-19 (Coronavirus) through a city. You can implement poli ... Read more
This simulator looks at the spread of COVID-19 (Coronavirus) through a city. You can implement policies, change assumptions about the disease and see the impacts in realtime.
sim67855 runs
Biology Science Education COVID-19 Coronavirus
98527.9
#4

Enzyme Diversity: Enzymes, Products, and Substrates

sim227231 runs
enzymes substrates products DNA trypsin
94581.5
#5

Cellular Respiration Accounting Model

The purpose of the model is to understand how glucose is metabolized, and how the energy stored in i ... Read more
The purpose of the model is to understand how glucose is metabolized, and how the energy stored in its chemical bonds is transfered.
sim137375 runs
cellular respiration aerobic respiration ATP biology
83346.8
#6

Growth Factors, Cyclins, and Cancer

Explores the feedback loops that regulate the cell cycle. Model focuses on manipulating stimuli (gro ... Read more
Explores the feedback loops that regulate the cell cycle. Model focuses on manipulating stimuli (growth factors), to stimulate the cell cycle feedback loops.
sim101814 runs
growth factors cyclins cell cycle cancer
70925.8
#7

Lactase with Variable Sample Sizes

Arrayed Lactase Model
sim265333 runs
Lactase array sample size biology
57086.1
#8

Lactose Operon: An Inducible System

In this simulation users explore the negative feedback system of the Lactose Operon found in bacteri ... Read more
In this simulation users explore the negative feedback system of the Lactose Operon found in bacteria. Lactose induces the system by inhibiting and inhibitor.
sim58144 runs
Inhibition negative feedback biology lactose operon
55977.3
#9

Predator-Prey-LevelA

Level A: Up and Down in the Wild: Predator and Prey This lesson allows students to explore the in ... Read more
Level A: Up and Down in the Wild: Predator and Prey This lesson allows students to explore the interactions of two animal populations (wolves and moose) within an ecosystem. One animal in the simulation is a predator. The other animal is its prey. Their populations rise and fall (oscillate) over time as they interact and impact one another.
sim50998 runs, 48 downloads
Download Model
ecosystem population predator prey oscillation
54817
#10

Apterous Genetics

Apterous is an allele that results in a fly without wings. Wild-type variants have normally function ... Read more
Apterous is an allele that results in a fly without wings. Wild-type variants have normally functioning wings. The goal of this simulation is to determine the pattern of inheritance for the apterous phenotype. Is apterous dominant or recessive? Sex-linked or autosomal? Complete, incomplete, or codominant?
sim111906 runs
Genetics
50209.4
#11

Photosynthesis Model

sim227519 runs
49968.5
#12

Neurophysiology and Neurotoxicity

The main dependent variable measured in the model is the membrane potential (millivolts) of a motor ... Read more
The main dependent variable measured in the model is the membrane potential (millivolts) of a motor neuron and the muscle fiber it innervates. You will be able to add excitatory and inhibitory neurotransmitters, and compare how neurotransmitters modulate the electrical impulses of the motor neuron and the muscle fiber. Additionally, you will be able to compare the effects of four neurotoxins: Tetrodotoxin, botulinum toxin, sarin nerve gas, and VX. While extremely lethal, these toxins are very instructive in understanding neurons because of the specific way the toxins act. Each toxin modifies or inhibits a specific molecule in neurons that help process and transmit information.
sim30452 runs
Neurophysiology toxins sarin VX TTX
45152.9
#13

Model 2. Drug Transporters

This simulation shows the location and functioning of the major clinically important drug transporte ... Read more
This simulation shows the location and functioning of the major clinically important drug transporters in the : gastrointestinal membrane; renal tubular membrane; and the membranes of the hepatocyte. Simulations demonstrate their functioning after oral and intravenous doses of a drug substrate
sim29269 runs
drug transporters efflux uptake drug absorption
42870.4
#14

Enzyme Diversity

sim113819 runs
enzyme biology substrate pepsin indicators
42439.1
#15

College Loans

Each year, the cost of a college education continues to rise and more and more students must turn to ... Read more
Each year, the cost of a college education continues to rise and more and more students must turn to student loans to complete their education. But as graduates leave college to embark on their careers, they face an almost Sisyphean struggle with student debt, forever facing an uphill battle while carrying a heavy burden, only to find they are getting nowhere! Whether you are graduating from college or just entering, we hope this model will enable you to better understand student loans and help plan for your future.
sim22401 runs, 688 downloads
Download Model
Student loans loans college interest repayment
38831.5
#16

Population dynamics of white footed mouse

sim239405 runs
32322.8
#17

Vacation

Do you ever feel like work is taking over your life? Burnout is generally characterized as a state o ... Read more
Do you ever feel like work is taking over your life? Burnout is generally characterized as a state of mental and physical exhaustion resulting in low productivity and de-personalization and is most likely caused by prolonged stress that does not dissipate. There are many different aspects that affect both the building and dissipation of burnout. This model focuses on workloads and vacations to see how they contribute to both your level of burnout and productivity. Use this model to ask questions about your workload and any benefits you would receive from taking a vacation. What happens when you suddenly have a bigger workload? What happens when work piles up? Does vacation increase or decrease your stress levels?
sim15718 runs, 291 downloads
Download Model
Vacation burnout stress productivity workload
31875.1
#18

Evolution and Natural Selection

sim160795 runs
27953.8
#19

Zombie Apocalypse

This is our first model in the From Imagination to Simulation series. It is a nod to the Halloween s ... Read more
This is our first model in the From Imagination to Simulation series. It is a nod to the Halloween season and investigates a zombie apocalypse! Our fascination with zombies continually grows with the help of movies, TV shows, and books that give a wide range of zombie possibilities. But what are the dynamics behind a zombie epidemic? This model will specifically look at the spread of a zombie outbreak and examine some of the variables that help and hinder the rate of infection. We hope you will continue to see the benefits and versatility of Systems Thinking and enjoy our new series, From Imagination to Simulation! Continue to ponder those out-of-the-ordinary problems. They may seem unrealistic, but perhaps some of their dynamics may resonate with reality. Check out our zombie apocalypse model to see if there is any chance for human survival!
sim12133 runs, 373 downloads
Download Model
Systems Thinking zombies epidemic disease susceptible
27866.6
#20

Cellular Respiration Inquiry

Model of the dynamics of the metabolism of one mole of glucose. Randomness is built into the computa ... Read more
Model of the dynamics of the metabolism of one mole of glucose. Randomness is built into the computations.
sim40032 runs
metabolism respriation ATP biology
27849.8
#21

Lac Operon with Monod Bump

sim60121 runs
Lac Operon Gene Regulation mRNA
26653.7
#22

Photosynthesis Simulation with Variance

sim207024 runs
24298.7
#23

Limiting Nutrients in Aquatic Ecosystems

Experiment with a variety of nutrients that are limited by different degrees in four different ecosy ... Read more
Experiment with a variety of nutrients that are limited by different degrees in four different ecosystems.
sim40766 runs
limiting nutrients ecosystem biology logistic growth
22352.2
#24

Administration routes

observe three type of plasma concentration curve, and combine three of them
sim10809 runs
Pharmacokinetics intra venous bolus div p.o.
21066.4
#25

Evolution of LAP Allele in Mussels

sim42691 runs
Evolution Natural Selection Cline
18359.5
#26

Lotka-Volterra Predator-Prey Model

Explore my favorite aspect of system dynamics and a historic example. The homeostasis generated by t ... Read more
Explore my favorite aspect of system dynamics and a historic example. The homeostasis generated by the interconnections of a negative feedback loop governs much of life.
sim62431 runs
negative feedback loop Lotka-Volterra homeostasis predator-prey
18095.8
#27

Closed Loop

Mininimal closed-loop model of the cardiovascular system
sim64429 runs
16728.5
#28

White-Eyed Genetics

White-eyed is an allele that results in a fly white eyes. Wild-type variants have red eyes. The ... Read more
White-eyed is an allele that results in a fly white eyes. Wild-type variants have red eyes. The goal of this simulation is to determine the pattern of inheritance for the white-eyed phenotype. Is yellow body dominant or recessive? Sex-linked or autosomal? Complete, incomplete, or codominant?
sim38272 runs
Genetics
15157.4
#29

Oral Absorption

This model is based on first order absoprtion in a 1-compartment model
sim19646 runs, 64 downloads
Download Model
Drug Absoprtion Bioavailability Bioequivalence
13391.8
#30

Diffusion of a Spherical Cell

Why are cells small? This model allows users to see how the size of a sphere affects the rate of dif ... Read more
Why are cells small? This model allows users to see how the size of a sphere affects the rate of diffusion.
sim59021 runs
diffusion surface area volume radius
12697.5
#31

Transformation Simulation

Simulation allows students to test the transformation principle. Two major goals of the experiment a ... Read more
Simulation allows students to test the transformation principle. Two major goals of the experiment are: 1. Allow users to see that supernatant from heat-killed bacteria can transform the genes of another bacterium. 2. What transforms the inheritance of the bacteria is DNA, not RNA or proteins.
sim20657 runs
transformation DNA biology
11900.9
#32

Thyroid Hormone - Negative Feedback

sim15119 runs
negative feedback thyroid hormone metabolism biology
11475
#33

Intravenous Infusion

This model demonstrates the pharmacokinetic characteristics of constant continuous drug administrati ... Read more
This model demonstrates the pharmacokinetic characteristics of constant continuous drug administration.
sim8622 runs, 31 downloads
Download Model
drug pharmacokinetics intravenous infusion zero order input constant continuous drug administration
11385
#34

Recombination and Gene Linkage

sim46931 runs
10396.5
#35
sim21061 runs, 1 download
SDG policy integration coherence simulation
10299
#36

Pharmacokinetics: An IV Injection on a Two Compartment Model

This model shows the profile of a drug after an intravenous injection when the drug displays two com ... Read more
This model shows the profile of a drug after an intravenous injection when the drug displays two compartment characteristics
sim9604 runs, 42 downloads
Download Model
durg pharmacokinetics IV two compartment model
9914.28
#37

Understanding Restrictive and Nonrestrictive Hepatic Clearance

Many drugs are removed from the body by metabolism in the liver. A drug's hepatic clearance is a me ... Read more
Many drugs are removed from the body by metabolism in the liver. A drug's hepatic clearance is a measure of the liver's ability to metabolize a drug. This simulation demonstrates the characteristics of high extraction (nonrestrictive clearance, low extraction (restrictive clearance and intermediate clearance.
sim5127 runs
drug metabolism clearance elimination restrictive clearance
9844.31
#38

Water Potential and Osmosis

Factors that affect the flow across a semi-permeable membrane.
sim142018 runs
9492.25
#39

Mulitple Bolus Injections Pharmacokinetics

This model shows the typical plasma concentration profile associated with the administration of seve ... Read more
This model shows the typical plasma concentration profile associated with the administration of several doses of a drug over time. It demonstrates the determinants of the fluctuation in the plasma concentrations, the accumulation of the drug over the course of therapy and the resting steady state plasma concentrations.
sim6413 runs, 32 downloads
Download Model
drug pharmacokinetics multiple doses multiple intravenous bolus injections
9209.33
#40

2019 Step1

Step1
sim28823 runs
intravenous oral theophylline
8361.96
#41

Automation

Innovation often raises concerns about job losses, increasingly so in the past century with widespre ... Read more
Innovation often raises concerns about job losses, increasingly so in the past century with widespread automation and advanced artificial intelligence. Should we start to fear for our job security or will the creative potential in society maintain the labor force? Explore this model to see some of the interesting possibilities!
sim3376 runs, 239 downloads
Download Model
Automation job loss AI artificial intelligence labor force
8338.79
#42

Multiple Oral Doses Pharmacokinetics

Most commonly people take oral doses of a drug over an extended period. This model demonstrates the ... Read more
Most commonly people take oral doses of a drug over an extended period. This model demonstrates the unique plasma concentration profile associated with this type of drug administration. The model assumes first-order drug absorption with no lag time. Simulations can be carried out to observe how the rate and extent of absorption (bioavailability) affect the profile.
sim4980 runs, 29 downloads
Download Model
multiple oral doses interactive pharmacokinetics drug bioavailability
8044.38
#43

Nonlinear Pharmacokinetics and Phenytoin

Nonlinear or capacity limited pharmacokinetics can occur whenever a process involved in the absorpti ... Read more
Nonlinear or capacity limited pharmacokinetics can occur whenever a process involved in the absorption, distribution or elimination of a drug becomes saturated. This model demonstrates nonlinear elimination (metabolism) using phenytoin as the model drug. Specifically, it demonstrates how increasing doses of the drug produce disproportionate increases in the plasma concentration. It also demonstrates how the model parameters, Km and Vmax influence of the plasma concentration -time profile.
sim4486 runs, 30 downloads
Download Model
nonlinear pharmacokinetics capacity limited elimination drug phenytoin
8019.7
#44

Model 1. Introduction to PK and PD

This model allows users to use trial and error to identify appropriate doses of a drug for IV, oral ... Read more
This model allows users to use trial and error to identify appropriate doses of a drug for IV, oral and other extravascular routes of administration
sim11928 runs
Pharmacokinetics Pharmacodynamics Therapeutic Range
7962.84
#45

COVID-19 Model

This simulator walks the user through a model showing the spread of the COVID, or Corona Virus throu ... Read more
This simulator walks the user through a model showing the spread of the COVID, or Corona Virus through a city. You can implement policies, change assumptions about the disease and see the impacts in realtime.
model6142 downloads
Download Model
Biology Science Education COVID-19 Corona Virus
7619.91
#46

Oxytocin and Child Birth

sim57330 runs
7175.1
#47

Understanding the Measles Outbreak

The current 2019 measles outbreak is the highest since the early '90s and is drawing much attention ... Read more
The current 2019 measles outbreak is the highest since the early '90s and is drawing much attention from the media and the public. This model walks investigates how measles spreads in a population and what policies work best for reducing that spread.
sim3698 runs, 236 downloads
Download Model
Measles vaccine infectious disease quarantine WOM
6767
#48

Circadian Clock in the Mouse

Transcriptional Translational Feedback Loop in the Mouse
sim15294 runs
Mouse Circadian Clock
6287.12
#49

The Power of The Missing Middle

Systems Thinking at Large takes a closer look at the suprising win for Trump. Focusing on the missi ... Read more
Systems Thinking at Large takes a closer look at the suprising win for Trump. Focusing on the missing middle population and their possible power in the voting booth.
sim2297 runs, 157 downloads
Download Model
Trump missing middle vicious cycle storytelling manufacturing jobs
6145.96
#50

Choosing the Future

Users can run 3 long term scenarios for the Canadian economy featured in Managing without Growth (2n ... Read more
Users can run 3 long term scenarios for the Canadian economy featured in Managing without Growth (2nd edition) and create their own
sim3539 runs
economic growth post-growth no growth sustainable prosperity environment
6118.61
#51

The dynamics of photosynthesis - variable sample size

The dynamics of photosynthesis - variable sample size
sim12610 runs
photosynthesis sample size biology
6107.4
#52

Phenology of the Karner Blue Butterfly

Karner Blue butterfly is an endangered species. Habitat loss and climate change are contributing fac ... Read more
Karner Blue butterfly is an endangered species. Habitat loss and climate change are contributing factors to the reduction in the butterflies' population sizes. Climate change can alter the timing of lifecycles. When climate change disproportionally affects the timing of life cycles of species in an ecosystem asynchrony within a food web occurs.
sim6460 runs
asynchrony timing phenology climate change butterfly
6075.11
#53

Guppy Evolution

sim31597 runs
evolution biology genes
6039.34
#54

Dosing regimen for renal failure

compare plasma concentration in renal failure, plan the dosing regimen in renal failure
sim3576 runs
Pharmacokinetics creatinine clearance Scr Clcr aminoglycoside
5986.25
#55

Guns At School

This interface explores the public policy issue of gun violence at schools. As a policymaker, you c ... Read more
This interface explores the public policy issue of gun violence at schools. As a policymaker, you can explore different initiatives to see which are most effective at reducing this violence.
sim5489 runs
Guns Schools Public Policy Violence Bullying
5663.24
#56

Simple Genetics

sim27961 runs
5645.78
#57

Predator-Prey-LevelC

sim6680 runs, 5 downloads
Download Model
ecosystem predator prey oscillation balance
5290.91
#58

Tryptophan Operon: A repressible system

sim22831 runs
5144.5
#59

Photosynthesis with Variable Sample Sizes

Sample sizes of Photosynthesis stocks in an array
sim31748 runs, 49 downloads
Download Model
4879.27
#60

Housing Supply and Demand

Use this learning lab to investigate the housing crisis. Play with interest rates as if you are Chai ... Read more
Use this learning lab to investigate the housing crisis. Play with interest rates as if you are Chairman of the Federal Reserve and see the impact on housing supply and demand. What happens when banks relax mortgage requirements and more people qualify to buy homes?
sim2402 runs, 381 downloads
Download Model
Modules finance debt economics housing demand
4722
#61

Pattern with recessive single band

sim26023 runs
genetics
4556.12
#62

Steady State in Freshwater Ecosystems

sim21516 runs
4370.22
#63

Headcount Strategy

Explore a consulting firm’s headcount strategy. Understand the relationship between growth rates, pr ... Read more
Explore a consulting firm’s headcount strategy. Understand the relationship between growth rates, promotion times, headcount pyramid ratios, and attrition rates. This model is based on actual work that was done with a very well-known consulting company (here, code-named TWBC, Inc.). The firm's strategic goals were well-articulated, and each made sense when written down in a list on a piece of paper. However, when subjected to the more rigorous, dynamic scrutiny that an iThink modeling effort provides, the goals (as is too often the case) turned out to be in conflict with one another--stimulating actions that worked at cross-purposes. Efforts to achieve one goal drove the firm farther away from achieving the others. The subsequent analysis conducted with the model also pointed the way toward resolving the internal strategic inconsistencies and putting the firm back onto a strategically sound growth path.
sim1842 runs, 277 downloads
Download Model
Headcount employees growth manager consultant
4313.16
#64

COVID-19: Vertical Isolation in Brazil

Does the policy of vertical isolation allow a country to reopen its businesses and schools without i ... Read more
Does the policy of vertical isolation allow a country to reopen its businesses and schools without increasing COVID-19 cases or deaths? This simulator explores the outcomes of horizontal isolation (what we're doing now) and vertical isolation (only isolate the sick and the elderly).
sim3556 runs
Biology Science Education COVID-19 coronavirus
4261.67
#65

Multiple Intermittent Infusions Pharmacokinetics

The model shows the unique plasma concentration-time profile associated with the administration of a ... Read more
The model shows the unique plasma concentration-time profile associated with the administration of a drug using multiple short infusions. It demonstrates the influence of the duration of the infusion and allows the user to practice the calculation of a suitable dose and dosing interval to achieve desired peak and trough plasma concentrations of a drug.
sim2199 runs, 21 downloads
Download Model
Multiple intermittent infusions aminoglycoside infusion drug interactive pharmacokinetics
4085.29
#66

Change the dosing interval

interval & dosing, regularly or irregularly
sim2917 runs
Pharmacokinetics dosing interval irregular interval TMU Hara
3880.83
#67

Pharmacokinetics: An IV Injection in a 1-Compartment Model

sim15879 runs, 66 downloads
Download Model
3659.24
#68

Pulmonary Edema

This model predicts collection of fluid in the lungs.
sim13976 runs
3620.69
#69

Limits to Growth Archetype

Shifting loop dominance in a limits-to-growth archetype is examined using the Hayward/Boswell Loop I ... Read more
Shifting loop dominance in a limits-to-growth archetype is examined using the Hayward/Boswell Loop Impact Method.
sim1748 runs, 151 downloads
Download Model
Business Loop Dominance Limits to Growth Shifting loop dominance Urban Dyanmics
3498.19
#70

Populations-LevelC

The behavior over time of a population limited by density-dependent factors is called logistic growt ... Read more
The behavior over time of a population limited by density-dependent factors is called logistic growth. You will be simulating a model of logistic population growth. You'll be able to change factors that address how fast an animal population grows, how long individuals in the population live on average, and how much area the population has available. See if you can vary the shape of the logistic curve, or create something different.
sim4513 runs, 25 downloads
Download Model
populations logistic
3402.96
#71

Biomass Accumulation Model

Learn to use a simple computer model to predict biomass and carbon storage for any geographical biom ... Read more
Learn to use a simple computer model to predict biomass and carbon storage for any geographical biome. Learn more at www.globe.gov (The GLOBE Program).
sim2850 runs
biomass biomass accumulation carbon cycle globe npp
3226.26
#72

HPV and Adaptive Immune Response

sim4238 runs
HPV Antibodies feedback loops vaccine
3043.92
#73

Dairy Cows

Agriculture offers many modeling opportunities. In this Systems in Focus, we look at the life cycle ... Read more
Agriculture offers many modeling opportunities. In this Systems in Focus, we look at the life cycle of a dairy herd, including milk production. This model could be used as the basis for methane production control, trade agreements about milk and how that impacts herd size, increasing production with demand, etc. Visit https://iseesystems.com/resources/systems-in-focus/agriculture/ for more information.
model2439 downloads
Download Model
Systems in Focus agriculture cows dairy
3008.14
#74

Evolution with Heterozygous Advantage

Evolution of Populations: Genetic Drift, Natural Selection, and Mutations
sim4899 runs
evolution natural selection genetic drift
2981.24
#75

Predator-Prey-Biomass-LevelC

Level C: Eat and Be Eaten: Prey as Predator, Predator as Prey This model explores a moose and wol ... Read more
Level C: Eat and Be Eaten: Prey as Predator, Predator as Prey This model explores a moose and wolf population. A predator/prey relationship is present, as with Lesson 4, but now the moose have a food source, creating a more realistic representation of the ecosystem. Students take on the role of wildlife manager and control hunting policies for both predator and prey populations. The default simulation behavior for prey, predators, and biomass is oscillation. Depending on policy decisions, a variety of results occur.
sim2033 runs, 23 downloads
Download Model
science ecosystem oscillation predator prey
2687.84
#76

Urban Business Expansion

The business sector of the Three Stock Urban Dynamics model is examined using the Hayward/Boswell Lo ... Read more
The business sector of the Three Stock Urban Dynamics model is examined using the Hayward/Boswell Loop Impact Method.
sim1310 runs, 96 downloads
Download Model
Loop Dominance Limits to Growth Shifting loop dominance Urban Dyanmics Loop Impact
2635.37
#77

Humanitarian Aid

A look at disaster relief under uncertain local government scenarios. It looks at how long it might ... Read more
A look at disaster relief under uncertain local government scenarios. It looks at how long it might take to establish clean water thru flying in bottled water and constructing wells. There is also the impact on spread of disease and survival due to lack of water. Created by Mark Heffernan and George McDonnel
sim1592 runs, 173 downloads
Download Model
Disaster relieft Water Mark Heffernan George McDonnel scenarios
2627.25
#78

COVID-19: Role of hospitals, soc. dist., and vaccines

sim2151 runs
Environment Biology Business Technology Science
2508.72
#79

Catastrophic Regime Change in Aquatic Ecosystems

sim22890 runs
Ecology
2476.12
#80

Global Carbon Cycle Model with Feedbacks

The Global Carbon Cycle Model with Feedbacks builds on the Simple Global Carbon Cycle Model by inclu ... Read more
The Global Carbon Cycle Model with Feedbacks builds on the Simple Global Carbon Cycle Model by including ecosystem feedbacks as well as new parameters such as CO2 and temperature effects, more carbon pools, and marine biota. Use this model to explore how carbon moves through the Earth system, how the pools and fluxes interact, and how human actions can impact the carbon cycle. Learn more at www.globe.gov (The GLOBE Program) Use this model to explore how carbon moves through the Earth system, how the pools and fluxes interact, and how human actions can impact the carbon cycle. Learn more at www.globe.gov (The GLOBE Program)
sim1844 runs
carbon carbon cycle global globe feedbacks
2446.44
#81

Sigmoidal Emax Model of Drug Response

This is the model that is most commonly used to for the time course of drug effects in man. It assum ... Read more
This is the model that is most commonly used to for the time course of drug effects in man. It assumes that the response is driven by the blood or plasma concentrations of the drug. When the model parameters are known, it can be used to predict response at anytime time after any dose.
sim3178 runs, 44 downloads
Download Model
Pharmacodynamic Drug Sigmoidal Emax Emax
2401.55
#82

H1N1 Flu Outbreak

What is most effective in controlling the outbreak of a flu virus in schools? Is it better to vaccin ... Read more
What is most effective in controlling the outbreak of a flu virus in schools? Is it better to vaccinate or stay home? Use this Learning Lab to understand how infectious disease spreads and why the World Health Organization signaled the 2009 H1N1 (also called “swine flu”) outbreak as a pandemic.
sim1519 runs, 178 downloads
Download Model
Flu outbreak SIR model infections desease pandemic
2202.26
#83

Business Cycle Dynamics

Business cycles are a fact of life for many industries. Market demand peaks one year only to plummet ... Read more
Business cycles are a fact of life for many industries. Market demand peaks one year only to plummet a year or two later. In this case study of a semiconductor business, Henk Akkermans, Professor of Supply Network Dynamics at Tilburg University, explores different policy options for order handling, production planning and capacity management to reduce oscillation and improve system performance.
sim895 runs, 283 downloads
Download Model
supply chain semiconductor oscillation. production planning capacity management
2110.18
#84

Stella Architect B.M. Sample

Este modelo es un primer intento de utilizar el "Business Canvas" desarrollado por Alexander Osterwa ... Read more
Este modelo es un primer intento de utilizar el "Business Canvas" desarrollado por Alexander Osterwalder e Yves Pigneur, para explicar su carácter sistémico mediante la simulación de un modelo de negocio genérico utilizando Stella Architect. El objetivo principal es mostrar el vínculo entre los conceptos del pensamiento sistémico y la práctica del "Systems Dynamics" con el ampliamente difundido "Business Canvas". En la narrativa utilizada para describir la construcción del diagrama "Stock & Flow", se denomina entre parentesis el tipo de componente (Stock, Flow, Converter, o Conector) correspondiente a los principales elementos del modelo de negocio. La simulación permite visualizar la naturaleza sistémica de un modelo de negocio representado mediante el "Business Canvas".
sim502 runs, 88 downloads
Download Model
Stella Architect Business Canvas Modelos de Negocios Alex Osterwalder Simulación
2109.47
#85

Populations-LevelA

Part of the osillation series, this simulation explores populations with a carrying capacity (one th ... Read more
Part of the osillation series, this simulation explores populations with a carrying capacity (one that does not oscillate because it has just one stock).
sim4415 runs, 16 downloads
Download Model
population ecology
2101.6
#86

Airport Runway Capacity

Examine the implications of an increasing number of landing airplanes on a fixed capacity runway.
sim1035 runs, 235 downloads
Download Model
Reengineering discrete modeling queues iThink process improvement
2075.09
#87

Dynaville

Dynaville simule l'évolution des habitants d'un territoire à un horizon de 10 ans (ménages, déplacem ... Read more
Dynaville simule l'évolution des habitants d'un territoire à un horizon de 10 ans (ménages, déplacements...), selon différents scénarios de logements, d'emplois et d'évolution de son attractivité.
sim1101 runs
attractivité territoire habitants démographie politique de logements déplacements
2071.37
#88

Extended Agrarian Society (from Dynamic Systems)

This model is an extension of the Simple Agrarian Society model from Dynamic Systems. The extensions ... Read more
This model is an extension of the Simple Agrarian Society model from Dynamic Systems. The extensions are to add a CO2 cost to the industrialization, an impact of CO2 on global temperature, an impact of global temperature on drought frequency, and impact of drought on food production and an impact of global temperature on polar sea ice.
model946 downloads
Download Model
population agriculture industrialization climate ice sheet
2068.91
#89

Macromodel

Model for the public policy testing
sim7802 runs, 29 downloads
Download Model
2025.33
#90

HPV with Influenza A Humoral Immunity

Immune response of HPV
sim6144 runs
HPV antibodies biology Immunity
1992.32
#91

Genotyping with Electrophoresis

sim5241 runs
biology inheritance DNA restriction enzyme
1966.98
#92

Extinction Vortex

sim10697 runs
1888.52
#93

Tesing Unknown Enzymes

sim38821 runs
enzymes
1804.54
#94

Beta Cell Simulation - Split story

sim10872 runs
1761.38
#95

System Dynamics of Carbon Budget

Simulation of the system dynamics of the global carbon dioxide budget based on the work on systems d ... Read more
Simulation of the system dynamics of the global carbon dioxide budget based on the work on systems dynamics based on John Sternman (MIT) and Krytyna Stave (University of Nebraska)
sim9249 runs
system dynamics carbon climate
1704.22
#96

Health Policy Management Flight Simulator

by Shamim
This is a basic health policy simulator that allows the user a policy lever on where to prioritise h ... Read more
This is a basic health policy simulator that allows the user a policy lever on where to prioritise health care spending.
sim2748 runs
health systems shifting boat
1674.28
#97

macrolab2017

sim6448 runs
1630.86
#98

Simple Global Carbon Cycle Model

The Global Carbon Cycle Model is a 5-box model, which includes five of the major carbon pools (atmos ... Read more
The Global Carbon Cycle Model is a 5-box model, which includes five of the major carbon pools (atmosphere, plants, oceans, soils, and fossil fuels), and the fluxes between them. Use the Global Carbon Cycle Model to explore how carbon moves throughout the Earth system, how different pools and fluxes interact, and the impacts of human actions on the carbon cycle. Learn more at www.globe.gov (the GLOBE Program).
sim1760 runs
carbon cycle carbon global globe simple
1547.51
#99

Weight Loss Sim

by Corne
This simulation gives the user the ability to specify their own current condition (weight, age, heig ... Read more
This simulation gives the user the ability to specify their own current condition (weight, age, height etc.), choose their exercise regime and eating plans. The simulator then gives a projection for the user's weight for the next year (at a weekly resolution). Please take note that most of the pictures are navigation buttons to different screens, so remember to click on the pictures. I have personally used this simulator to successfully lose more than 20 kg. Hope you find this as valuable as I did. Good luck with your weight journey!
sim1921 runs
Weight loss Health
1546.42
#100

Story of the Month Reissue: Deficit

Examines the often-confused concepts of deficits versus surpluses and tax cuts versus tax rebates.
sim805 runs, 51 downloads
Download Model
tax cuts tax rebates deficit surplus social security
1432.23
#101

Evolving Bits

Diversity and selection for the basis of evolution. This simple model tries to illustrate these conc ... Read more
Diversity and selection for the basis of evolution. This simple model tries to illustrate these concepts.
sim1438 runs
Diversity Selection Evolution Receptor Antigen
1432.19
#102

Take the Infusion Challenge

Use this model to see if you can use a drug's pharmacokinetic and pharmacodynamic properties to dete ... Read more
Use this model to see if you can use a drug's pharmacokinetic and pharmacodynamic properties to determine the initial rate of drug administration. See if you can identify potential drug-drug interactions and respond when appropriate by making appropriate modifications to the dose.
sim1477 runs
Dosing Drug Pharmacokinetics Constant Continuous Input
1406.88
#103

SysQ

An Introduction to SysQ is our free interactive resource for building and applying Systemic Intellig ... Read more
An Introduction to SysQ is our free interactive resource for building and applying Systemic Intelligence (SysQ). By using this guide, practitioners of systems thinking and adaptive leadership will better understand why systemic intelligence is an essential leadership capacity and how to increase anyone's (or any team’s) ability to apply it. An Introduction to SysQ gives you rapid access to the full suite of systems thinking tools (including the SysQ Questions, trend graphs, archetypes, causal loop and stock & flow diagrams, and simulations) – including when and how to use each! And because the guide is browser based, it works on mobile devices! You can even embed it on your website. We believe you’ll find this resource so useful that you’ll decide it belongs in your browser’s favorite bookmarks! (Currently, it works best on Google applications and devices – Chrome and Android-based devices.)
sim642 runs
systems thinking system dynamics sysq resource guide
1387.77
#104

SellPhone solo

The Sim is part of the book "Growth Dynamics in New Markets" (https://onlinelibrary.wiley.com/doi/bo ... Read more
The Sim is part of the book "Growth Dynamics in New Markets" (https://onlinelibrary.wiley.com/doi/book/10.1002/9781119118305). This version is for playing alone, RivTel is played by the model (v3.3)
sim1053 runs
SellPhone Growth Diffusion Schaffernicht Groesser
1309.7
#105

Dynamic Modelling of Lionfish Invasion in the Caribbean Sea and Atlantic Ocean

The dynamic model shall explain the rapid diffusion of the lionfish - an invasive species - througho ... Read more
The dynamic model shall explain the rapid diffusion of the lionfish - an invasive species - throughout the Caribbean Sea and the Atlantic Ocean. The interface contains two explanatory models - a simple diffusion model and more realistic convection model - as well as a policy game to manage the regional countermeasures of local decision makers.
sim580 runs
lionfish invasion system dynamics caribbean
1288.29
#106

Energy Demand Lab

This simple model explores the demand dynamics for a state's energy usage. For three sectors (reside ... Read more
This simple model explores the demand dynamics for a state's energy usage. For three sectors (residential, industrial, and agricultural) you can adjust the size of initial user base, the growth rate for the number of users, and the rate for the change in demand per user.
sim518 runs, 290 downloads
Download Model
Energy residential industrial agricultural energy usage
1260.56
#107

traffic congestion

Explores the dynamics of road use and road construction.
model1918 downloads
Download Model
traffic urban planning congestion
1258.22
#108

The Laundry Detergent Game

Congratulations! You've just been hired by the major grocery chain The Price Shopper as head of mark ... Read more
Congratulations! You've just been hired by the major grocery chain The Price Shopper as head of marketing. Your job is to turn around The Price Shopper's dismal sales of laundry detergent. The big-wigs have given you 12 months and a marketing budget of up to $10,000 per month to spend as you please. They'll decide to keep you, or send you to the cleaners based on how much profit you bring in over the year. Do you think you can make the big MONEY?
sim826 runs, 74 downloads
Download Model
system dynamics bass diffusion model marketing
1250.42
#109

Physiologically Based Pharmacokinetic Model

This model shows how to build a PBPK model and how drug concentrations in different tissues can be s ... Read more
This model shows how to build a PBPK model and how drug concentrations in different tissues can be simulated
sim1060 runs
Drug Pharmacokinetic PBPK Physiologically Based Pharmacokinetic Model
1207.19
#110

Turchin’s Metaethnic Frontier Theory of Imperial Growth

A country builds its empire by attacking its neighbours and taking over both their land and their pe ... Read more
A country builds its empire by attacking its neighbours and taking over both their land and their people. The larger the empire becomes, the more resources they have available to take further territory by force. However the further they expand, the harder they find it to keep expanding due to the geographical and organisational logistics involved. Additionally the empire finds it harder to maintain social cooperation among its people, its asabiya.
sim290 runs, 63 downloads
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Turchin Empire Collapse Collins Geopolitical
1192.63
#111

SOP HABITUATION LAB ESP

Esta es una herramienta en línea de fuente abierta para aprender algunos de los principales aspectos ... Read more
Esta es una herramienta en línea de fuente abierta para aprender algunos de los principales aspectos teóricos y empíricos del análisis experimental de la habituación. La herramienta fue diseñada para combinar de datos y teoría a través de experimentos simulados. Las simulaciones ejemplifican cómo la teoría de la primacía de Allan Wagner da cuenta del conjunto de características empíricas de la habituación propuestas por Thompson y Spencer en 1966. Por medio de esta plataforma interactiva usted aprenderá acerca de los fundamentos de esta teoría y como logra explicar estas observaciones empíricas con distintos parámetros.
sim8631 runs
Biology Science Education SOP Habituation
1187.54
#112

Animal Temperature

Explore the laws of thermodynamics with this animal temperature model. As you experiment, think abo ... Read more
Explore the laws of thermodynamics with this animal temperature model. As you experiment, think about animal adaptations and consider the following: What problems do small animals face compared to large animals in hot and cold environments? What problems do cold-blooded (poiklothermic) animals face compared to warm-blooded (homeothermic) animals? What is it that insulation really does for animals? The story behind this model is explained in a chapter of Tracing Connections
sim478 runs, 67 downloads
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Thermodynamcis adaptation poiklothermic homeothermic Warm-blooded
1158.85
#113

Product Development Simulator

The Bass Model or Bass Diffusion Model was developed by Frank Bass and it consists of a simple diffe ... Read more
The Bass Model or Bass Diffusion Model was developed by Frank Bass and it consists of a simple differential equation that describes the process of how new products get adopted in a population. The model presents a rationale of how current adopters and potential adopters of a new product interact.
sim766 runs
product development game simulator bass diffusion marketing
1141.26
#114

Campus sexual assault

A very simple, one stock, simulation of campus sexist attitudes toward rape and initimate partner vi ... Read more
A very simple, one stock, simulation of campus sexist attitudes toward rape and initimate partner violence. The model was originally developed in 1998 and later translated into Stella. The model has a number of modeling errors, but at the time, proved useful for gaining insight into the dynamics of the system and developing an innovative prevention program.
sim1144 runs, 35 downloads
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campus sexual assault community norms
1139.49
#115

2019 Step2

dosing interval
sim7710 runs
regular irregular
1135.97
#116

Irreversible Drug Effects - Proton Pump Inhibitors

Some drugs act by binding covalently to their receptors. As a result, the target is destroyed and it ... Read more
Some drugs act by binding covalently to their receptors. As a result, the target is destroyed and its function returns only when it has been replaced by newly synthesized product. The target may be a protein, DNA, an enzyme, or a cell at any stage of development. This model has been applied to the action of the proton pump inhibitors, which bind to and destroy the H+,K+-ATPase pumps in the parietal cells of the gastric mucosa. Normal proton secretion is restored only when the pumps are replaced by newly synthesized functioning pumps (i.e., the usual turnover time of the system).
sim550 runs, 7 downloads
Download Model
Pharmacodynamic Irreversible Drug Effects Proton Pump Inhibitors PPI Response Model
1109.5
#117

SellPhone solo v2

The Sim is part of the book "Growth Dynamics in New Markets". You are the country manager of the mbi ... Read more
The Sim is part of the book "Growth Dynamics in New Markets". You are the country manager of the mbile phone company NewPhone and try to diffuse mobile telephony in the country Plutonia. Your competitor is RivTel, and they have the same goal. During 123 months, each of the managers can ser the values of five decision variables and try to acheive the highest possible accumulated profits. (https://onlinelibrary.wiley.com/doi/book/10.1002/9781119118305). This version is for playing alone, RivTel is played by the model (v2)
sim518 runs
SellPhone Growth dynamics Diffusion Martin Schaffernicht Stefan Groesser
1092.79
#118

UHE1

This sim supports exploration of the behaviour shown in Figure 4.3 of the book "Understanding Human ... Read more
This sim supports exploration of the behaviour shown in Figure 4.3 of the book "Understanding Human Ecology" by R. Dyball and B. Newell (2015)
sim1846 runs
system dynamics basic concepts
1005.26
#119

Evolution: Grants Finches

Models the effects on population sizes of ground finches with different beak sizes in response to di ... Read more
Models the effects on population sizes of ground finches with different beak sizes in response to different amounts of annual precipitation.
sim4080 runs
evolution biology natural selection
976.6
#120

BacterialGrowth

Yo listen up, here's the story About a little guy that lives in a blue world And all day and all n ... Read more
Yo listen up, here's the story About a little guy that lives in a blue world And all day and all night and everything he sees is just blue Like him, inside and outside Blue his house with a blue little window And a blue Corvette And everything is blue for him And himself and everybody around 'Cause he ain't got nobody to listen I'm blue da ba dee da ba daa Da ba dee da ba daa, da ba dee da ba daa, da ba dee da ba daa Da ba dee da ba daa, da ba dee da ba daa, da ba dee da ba daa I'm blue da ba dee da ba daa Da ba dee da ba daa, da ba dee da ba daa, da ba dee da ba daa Da ba dee da ba daa, da ba dee da ba daa, da ba dee da ba daa I have a blue house with a blue window Blue is the color of all that I wear Blue are the streets and all the trees are too I have a girlfriend and she is so blue Blue are the people here that walk around Blue like my Corvette, it's in and outside Blue are the words I say and what I think Blue are the feelings that live inside me I'm blue da ba dee da ba daa Da ba dee da ba daa, da ba dee da ba daa, da ba dee da ba daa Da ba dee da ba daa, da ba dee da ba daa, da ba dee da ba daa I'm blue da ba dee da ba daa Da ba dee da ba daa, da ba dee da ba daa, da ba dee da ba daa Da ba dee da ba daa, da ba dee da ba daa, da ba dee da ba daa I have a blue house with a blue window Blue is the color of all that I wear Blue are the streets and all the trees are too I have a girlfriend and she is so blue Blue are the people here that walk around Blue like my Corvette, it's in and outside Blue are the words I say and what I think Blue are the feelings that live inside me I'm blue da ba dee da ba daa Da ba dee da ba daa, da ba dee da ba daa, da ba dee da ba daa Da ba dee da ba daa, da ba dee da ba daa, da ba dee da ba daa I'm blue da ba dee da ba daa Da ba dee da ba daa, da ba dee da ba daa, da ba dee da ba daa Da ba dee da ba daa, da ba dee da ba daa, da ba dee da ba daa
model485 downloads
Download Model
972.055
#121

Abastecimento de Água

Demanda de água gera novos investimentos em infraestrutura de abastecimento
diagram981 downloads
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demanda de água abastecimento urbano investimentos
960.335
#122

Model 21. Emax Model of Drug Response With an Effect Compartment

This model demonstrates how an effect compartment can be added to a pharmacokinetic model to accommo ... Read more
This model demonstrates how an effect compartment can be added to a pharmacokinetic model to accommodate a delay in drug response caused by a slow distribution of a drug to its site of action. The simulation also explains hysteresis
sim1120 runs, 21 downloads
Download Model
Drug Hysteresis Effect Compartment Pharmacodynamics
958.132
#123

mse-litsim

Modelo de Simulación de Escenarios MSE-LITSIM
sim883 runs
gestión áreas litorales eutrofización estuarios humedales
957.55
#124

Indirect Effect Model 1

Some drugs do not directly produce the measured drug response. Instead they act upstream, and either ... Read more
Some drugs do not directly produce the measured drug response. Instead they act upstream, and either increase or decrease the amount of the entity that directly mediates the response (response variable). Indirect effect Model I can be used for drugs that inhibit the synthesis of the response variable. An example is warfarin which inhibits the synthesis of clotting factors.
sim939 runs, 14 downloads
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indirect effect warfarin inhibition of kin
956.993
#125

2019 Step3 renew

sim8287 runs
951.48
#126

The Shrimp Lab

“The Shrimp Commodity System Learning Lab” was designed for individuals seeking to build their syste ... Read more
“The Shrimp Commodity System Learning Lab” was designed for individuals seeking to build their systems thinking muscle and policy-design skills. It has been used successfully in undergraduate and graduate courses where business sustainability and/or system dynamics applications are emphasized. The format offers learners a progression of interactive experiences on which to build an understanding of the issues of the global shrimp industry system, including wild fisheries and aquaculture, its financial instability, the environmental issues it faces, and how individual policy alternatives can be tested, analyzed and combined to address industry performance. The Learning Lab has two learning pathways: The Systems Thinking Basics course shows the application of systems thinking and stock-flow mapping as tools to hypothesize and express underlying system feedback structures contributing to issues such as resource depletion and environmental pollution. The Policy and Scenarios Advanced course deepens understanding of systems behavioral patterns by presenting policies which address commodity systems behavior challenges and by using alternative scenarios dealing with market forces as tests. Students in a course could be asked to provide their recommendations for a policy set which best achieves multiple performance objectives: industry wide profit growth for the two industry sectors, achieve coastal effluents improvements, and avoid large oscillations of shrimp populations and resource depletion in the wild fishery. Additional information is available in the Technical Note (UVA-OM-1428) that offers information for individual preparation assignments, suggestions for Group workshop activities, helpful causality notes for instructors, and insights into policy analyses. To obtain this Note or request further information about related shrimp industry cases, (UVA OM 1388 and 1389), contact Darden Business Publishing at http://store.darden.virginia.edu/contactus The Learning Lab was developed by Chris Soderquist, Pontifex Consulting and Professor Robert D. Landel of the Darden School, University of Virginia and is based on original research from Donella Meadows Institute (formerly Sustainability Institute) and Pontifex Consulting. Copyright © 2009 by the University of Virginia Darden School Foundation, Charlottesville, VA.
sim268 runs
Environment Biology Business Economics Ecology
945.781
#127

Gora Model Balanced Scorecard

sim3912 runs
945.24
#128

Bed capacity model

stcs
sim676 runs, 57 downloads
Download Model
Bed Capacity Model Whole Systems
930.808
#129

Inventory Workforce Model

Oscillations in an Inventory Workforce model are examined using the Hayward/Boswell Loop Impact Meth ... Read more
Oscillations in an Inventory Workforce model are examined using the Hayward/Boswell Loop Impact Method.
sim417 runs, 139 downloads
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Loop Impact Loop Impact Workforce Inventory Control Oscillations
891.858
#130

Magallanes ESP

En este simulador, Usted juega el papel del director de una planta de producción de la emtresa magal ... Read more
En este simulador, Usted juega el papel del director de una planta de producción de la emtresa magallanes. Debe manejar el personal de venta y la capacidad de producción de modo a obtener un crecimiento fuerte y sostenido de las ventas.
sim544 runs
Magallanes Sobrecrecimiento y colapso Martin Schaffernicht Universidad de Talca
883.049
#131

Salmon Life Cycle Simulator

sim931 runs
Pacific salmon life cycle modeling water temperature stream flow
880.42
#132

Collins Theory of Geopolitics - Effect of War

The spread of an empire according to the theory of Randall Collins and equations of Peter Turchin
sim347 runs, 40 downloads
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war empire geopolitics collins turchin
857.672
#133

YVSP Neighborhood

A neighborhood scale version of the Youth Violence System Project Model
sim3327 runs
839.33
#134

SIR COVID-19 Coronavirus Simulation

sim4580 runs
Environment Biology Science Education SIR
830.52
#135

Financial instability

by Crelis
Market-capitalism typically goes through cycles of expansion and contraction. Every now and then, th ... Read more
Market-capitalism typically goes through cycles of expansion and contraction. Every now and then, these common economic cycles go off the hinges. They become unstable and can lead to recessions, crises and depressions—phenomena that economists typically look to exogenous forces to explain. Alternative, mostly Marxian and Keynesian, explanations for the instabilities have been sought within the structure of the economic system itself. One such explanation is provided by Steve Keen in his Goodwin-Minsky model. The model effectively mimics the dynamics of key indicators prior to, during and after the 2007/08 crisis. However, the model is also over-specified, highly sensitive to initial conditions and therefore more difficult to convey. In line with George Box’s plea for parsimony, this paper presents a more straightforward version of Keen’s model that remains consistent with its fundamental behaviour. The model also illustrates the potential for further dialogue between Marxian economics and system dynamics.
model284 downloads
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Financial instability Karl Marx Richard Goodwin Hyman Minsky Steve Keen
829.52
#136

COVID-19 Model By Age

This models the COVID-19 pandemic as an SEIR model disaggregated by age. DIfferent ages have differ ... Read more
This models the COVID-19 pandemic as an SEIR model disaggregated by age. DIfferent ages have different contact rates, death rates, and conformance to social distancing. A thrid-order material delay is used to create the distribution for the tie to become infected and the time to recover.
model701 downloads
Download Model
Biology Science Education COVID-19 Coronavirus
828.967
#137

Aquatic Trophic Productivity Model

The ATP model is a dynamic food web simulation model.
sim1164 runs
food webs river restoration fish biomass
822.873
#138

Evolving Bits N=40

sim1566 runs
evolution bits receptor substrate
820.76
#139

Supply and demand model

Supply and demand model
sim787 runs, 195 downloads
Download Model
Supply demand model money stella
805.836
#140

Logistic Growth Model and the Butterfly Effect

Model allows users to test the starting population size (N), the carrying capacity of the populatio ... Read more
Model allows users to test the starting population size (N), the carrying capacity of the population (K), and the intrinsic rate of growth (r max). Iterations are discrete, not continuous.
sim1720 runs
logistic growth carrying capacity
801.15
#141

Transit Compartment of Drug Action

Change image Submit your own comment on the simulation. Share Comment upgrade hosting plan d ... Read more
Change image Submit your own comment on the simulation. Share Comment upgrade hosting plan delete simulation Transit Compartment Model of Drug Response By Sara Rosenbaum Sim URL: https://forio.com/simulate/sarar/transit-compartment-model Sim access:Other authors can download source model Sim plan: Simulate Free Sim stats:This sim has been run 326 times. This simulation was uploaded to Forio Simulate with the isee NetSim software. More information can be found at iseesystems.com. Your Rating: 1 star2 star3 star4 star5 star Average Rating: rating(1) Click here to edit the description A delay in response to a drug can occur when it takes a long time for the drug’s initial effect to be translated into the final response (a long transduction process). The delayed response profile can be captured using a series of transit compartments.
sim560 runs, 23 downloads
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Pharmacodynamics Transit compartment Delayed drug action
796.125
#142

Model 17. DDI 5 Inhibition of Gut and Hepatic Metabolism

This model demonstrates the effect of an inhibiotr that acts on enzymes both the gastrointestinal me ... Read more
This model demonstrates the effect of an inhibiotr that acts on enzymes both the gastrointestinal membrane and the liver. It also demonstrates the effect of grapefruit juice on drugs netaboliized by CYP3A
sim456 runs
Intestinal extraction Fg DDI Drug interactions Grapefruit juice
794.397
#143

General Practice Advanced skill simulator

A model to explore changing roles within the advanced skilled workforce for General Practice in the ... Read more
A model to explore changing roles within the advanced skilled workforce for General Practice in the UK.
sim354 runs
Primary care workforce skills level strategic workforce planning Whole
791.562
#144

Integrated Population System

This model is a second extension of the Simple Agrarian model from Dynamic Systems that modifies the ... Read more
This model is a second extension of the Simple Agrarian model from Dynamic Systems that modifies the simple agrarian society model to include drought, industry produced CO2 and ice sheet dynamics. Primarily this is published as a test of porting from Stella 10.1 and learning how the new Stella Online operates. Several of the converter weights have been fine tuned to provide a better behaved model than the first adaptation. At some point a user interface and story will be added and the starting conditions calibrated to approximate treating Earth as an industrialized, agrarian society.
model309 downloads
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population agriculture industrialization climate ice sheet
784.381
#145

MNH Strategic Model

Strategic model of country-level policies to reduce maternal and neonatal mortality.
sim780 runs
global health maternal survival neonatal survival
761.988
#146

Dairy value chain development in Nicaragua

Dairy farmers in Matiguás, Nicaragua face feed system constraints that reduce their competitiveness. ... Read more
Dairy farmers in Matiguás, Nicaragua face feed system constraints that reduce their competitiveness. Conventional value chain analysis methods are unsuited to prioritize upgrading options. System dynamics modeling of the Matiguás dairy value chain was therefore used to quantify and analyse policy impacts. The model was constructed and tested with stakeholders in the Matiguás dairy value chain through group model building.
sim297 runs, 1 download
Dairy value chain Nicaragua interventions policy
750.937
#147

Fish Banks, Ltd.Game

by Saeed
In the Fish Banks, Ltd. game (originally developed as a board game by Professor Dennis L. Meadows in ... Read more
In the Fish Banks, Ltd. game (originally developed as a board game by Professor Dennis L. Meadows in 1986), teams of players manage their own fishing companies. At the beginning of the game, each fishing company has equal financial resources and fishing fleet. Each company has the same operating costs and technology. At the beginning of every simulated year, the companies make decisions about building, buying, and/or selling ships, whether to fish or not, and how far to send their fleet for fishing. The game's objective is to maximize total assets at the end of the simulation. The game developed here is a modified version of the Meadows' game as explained in the game rules.
sim242 runs
Environment Economics Ecology Education Dennis Meadows
728.34
#148

Carbon Budget Simulator

This model determines the number of years in which the global carbon budget will be exhausted. You s ... Read more
This model determines the number of years in which the global carbon budget will be exhausted. You set the carbon budget as a multiple of current carbon dioxide emissions. You choose a rate of economic growth and a rate of reduction in emissions intensity (emissions/GDP). The model puases when the carbon budget is exhausted. The model can be used to determine the exhaustion of national and regional carbon budgets as well following the same steps.
sim811 runs
Environment Technology Science Economics
722.692
#149

Dynaville-English

Simulation of a territory over a 10-year time horizon (inhabitants, students, households, journeys,. ... Read more
Simulation of a territory over a 10-year time horizon (inhabitants, students, households, journeys,...) according to different housing policies, job scenarios, taking into account the territory attractiveness.
sim397 runs
Area Attractiveness housing policy inhabitants demographics students
716.648
#150

Temperature Control

Conduct experiments and try to maintain a constant temperature in a house that uses a climate contro ... Read more
Conduct experiments and try to maintain a constant temperature in a house that uses a climate control system. Turn on and off the Proportional and Integral controllers that drive the heat pump. Experiment with different outside temperatures, and different thermostat settings. See what happens when you change the house's insulation by adjusting the temperature loss constant.
sim389 runs, 74 downloads
Download Model
Temperature proportional integral controller Newton's law heat pump
712.674
#151

Urban Stream Rainfall

A simple example of streamflow response to rainfall and basin percent urban area.
sim502 runs
rainfall-runoff modeling simulation urban peak-flow streamflow
702.201
#152

Amalgamated Industries

sim2524 runs, 179 downloads
Download Model
692.38
#153

Educational Outcomes

Educational outcomes in relation to resource allocation
model628 downloads
Download Model
Education resources funding student achievement
686.57
#154

The Wolves of Yellowstone

Keystone species are defined as a plant or animal that plays a unique role in the way the ecosystem ... Read more
Keystone species are defined as a plant or animal that plays a unique role in the way the ecosystem functions. But what would happen if that species were removed? What ripple effects would be caused by the absence of this species? We can examine these questions by looking at the wolf population in Yellowstone National Park. Wolves once flourished in Yellowstone and its surrounding areas. However, soon after the area was settled, misperceptions caused by fear and hatred fueled a large extermination effort of the wolves. For nearly 70 years, wolves were absent from Yellowstone. During this time, the ecosystem changed and diminished until scientists realized the value of the wolves and reintroduced them to Yellowstone. This model, built in iThink, uses storytelling to understand the dynamics of this keystone species. What animals were affected by their presence or absence. See how wolves play a part in not only population control of their prey but other animals and even plants far down the trophic levels.
sim23 runs, 295 downloads
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Keystone species Wolves wolf Trees Aspen
682.273
#155

Simulator private

sim2670 runs
678.22
#156

SellPhone Solo S

Versión en Español del simulador SellPhone, que complementa el libro docente "Growth dynamics in new ... Read more
Versión en Español del simulador SellPhone, que complementa el libro docente "Growth dynamics in new Markets" para los estudiantes de la Universidad de Talca
sim1363 runs
Schaffernicht Universidad de Talca
664.771
#157

Grit-Affect-Performance

by Raafat
A first attempt at conceptualizing the dynamic relationship between emotions and grit and their infl ... Read more
A first attempt at conceptualizing the dynamic relationship between emotions and grit and their influence on student performance in cyberlearning environments
model450 downloads
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learning support scaffold online science
651
#158

Leg VS Asprin

ur leg, vs, some asprin
model543 downloads
Download Model
leg asprin fight title fight fight for title
645.419
#159

Customer-Employee Satisfaction

Research shows a strong correlation between employee satisfaction and customer satisfaction. Underst ... Read more
Research shows a strong correlation between employee satisfaction and customer satisfaction. Understand the correlation through this model, which illustrates the causal relationship between the two.
sim304 runs, 191 downloads
Download Model
Customer satisfaction employee satisfaction human resourses
642.79
#160

Stella project

Simulation showing how cyber attacks have grown in various years.
model558 downloads
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amount of attacks attacks per year increase rate of attacks
641
#161

Service Call Center Dynamics

One organization in the service delivery business experienced a situation where the number of delive ... Read more
One organization in the service delivery business experienced a situation where the number of delivery requests increased dramatically due to a seasonal promotion. This increase in requests caused an overload on the service delivery staff by not only having more people requesting service, but also because the amount of time spent with each customer increased. This model is designed to describe why this occurred in a way that can be transferable to other service delivery organizations.
sim324 runs, 161 downloads
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discrete modeling queues conveyors cycle time
636.195
#162

Resource Allocation

One of the most challenging tasks in most organizations is the allocation of headcount between time- ... Read more
One of the most challenging tasks in most organizations is the allocation of headcount between time-competing activities. In this model, you will have a chance to explore these sorts of dynamics in the context of a consulting firm, where the same headcount can be allocated to business development activities and client service delivery. You'll see the classic pattern of "Feast or Famine," or the so-called "pig in a snake," emerge.
sim524 runs, 200 downloads
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human resources headcount
635.812
#163

Model 20. DDI Drug-Drug Interactions - Pharmacodynamic

This model demonstrates the interaction between two agonists and allows the efficacy (Emax) of one t ... Read more
This model demonstrates the interaction between two agonists and allows the efficacy (Emax) of one to be varied
model612 downloads
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Drug Interactions Pharmacodynamic Partial Agonist
630.202
#164

Emergency Room

This simulation shows the basic dynamics of a hospital emergency room. Patients arrive, are tre ... Read more
This simulation shows the basic dynamics of a hospital emergency room. Patients arrive, are treated and leave. You are able to control the average arrivial rate and average treatment time. This simulation was made using the 3rd party developer API embedded within Stella Architect.
sim441 runs
health hospital emergency room discrete event custom code
625.1
#165

Model 34. Fentanyl Induced Respiratory Depression and its Reversal With Naloxone

This models demonstrates the varying degrees of respiratory depression caused by fentanyl and its re ... Read more
This models demonstrates the varying degrees of respiratory depression caused by fentanyl and its reversal by naloxone. It also demonstrates that the action of naloxone is short lived and that additional doses may be needed
sim670 runs
Opioid opioid overdose naloxone Narcan
616.427
#166

Process with Complete Quality Control Feedback Mechanisms

This model depicts a process with exogenous inflows where the efficacy of the process descreases in ... Read more
This model depicts a process with exogenous inflows where the efficacy of the process descreases in proportion to time spent in the process. It is followed by a quality control mechanism with sensitivities and specificities which also decrease with time spent in the quality process. This bounded process and quality control is then checked against a gold standard which then adjusts as necessary in alignment with larger policy goals and feeds a larger data set. This model represents a realistic vision of what frontline quality control mechanisms should exist in the healthcare delivery system. It can be used as a tool for policy making to determine what acceptable rates of efficacy and outcome can be tolerated as quality based payments grow in popularity.
model209 downloads
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quality quality control quality based payments us healthcare policy rate dependent quality
614.68
#167

Multiple Retailer Supply Chain

Experience the dynamics of overshooting/undershooting inventory typical in the retail industry. Tour ... Read more
Experience the dynamics of overshooting/undershooting inventory typical in the retail industry. Tour this supply chain model to understand the structure from the factory through multiple retailers to the consumer.
sim210 runs, 217 downloads
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iThink inventory arrays conveyors supply chain
613.601
#168

Salmon Simulator

Simulation of salmon populations with harvesting using the Tucannon River (WA) as an example. Simul ... Read more
Simulation of salmon populations with harvesting using the Tucannon River (WA) as an example. Simulation accompanies the text Modeling the Environment, 2nd ed. by Andrew Ford. Used with permission.
sim648 runs
salmon harvesting maximum sustainable yield
610.312
#169

Kovid-19 Evde Kal!

sim497 runs
Biology Kovid 19 salgını 23 Mart (11. gün) evde kalmanın sağlık sistemi üzerindeki etkileri
607.287
#170

Wetland Forestland hydrology

Simulates multiple hydrological processes through a forestland and wetland on the Western Boreal Pla ... Read more
Simulates multiple hydrological processes through a forestland and wetland on the Western Boreal Plain, Canada
model553 downloads
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Precipitation Evaporation Infiltration Groundwater
602.993
#171

감염모델 (SIR Model) 2.0

기존 감염모델 연장선에서 작성했습니다. 따라서, 기존 모델과 설명이 이어집니다. 기존 모델을 확인하시기 바랍니다.
sim808 runs
Environment Biology Ecology Education
599.084
#172

Epidemic model for ISAT Spine version 3

Interactive Covid-19 pandemic model for the United States. The original model was used a signature ... Read more
Interactive Covid-19 pandemic model for the United States. The original model was used a signature project for ISAT 290. The model has been modified for Covid-19 and is being used in ISAT 390.
sim290 runs, 10 downloads
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Covid-19 pandemic system dynamics James Madison University School of Integrated Science and Technology
599.027
#173

Salmon Hypoxia Modeling Lab

This model simulates the influence of spawning salmon on dissolved oxygen in southeast Alaskan River ... Read more
This model simulates the influence of spawning salmon on dissolved oxygen in southeast Alaskan Rivers.
sim429 runs
Pacific salmon water quality dissolved oxygen hypoxia ecological modeling
597.812
#174

Building a Model of Church Growth Using System Dynamics

This simulation talks you through the steps involved in building a simple model of church growth and ... Read more
This simulation talks you through the steps involved in building a simple model of church growth and decline. System dynamics terms are explained. The consequences of hypotheses are examined as they are introduced.
sim599 runs, 6 downloads
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church growth word of mouth enthusiasts model construction Hayward
594.12
#175

COVID-19 Baseline Model Feedback Analysis

sim803 runs
Environment Biology Science Ecology Education
585.34
#176

Kent CC Cohort Test

Kent CC Test Cohort Model - Jan 18 v 1.4.2
sim2399 runs
569.82
#177

Supply Chain: Logistic Service Gas Station

This model was developed by Ernesto Vega and Ernesto Lagarda in 2017 for a Company AGM in Sonora Mex ... Read more
This model was developed by Ernesto Vega and Ernesto Lagarda in 2017 for a Company AGM in Sonora Mexico
model447 downloads
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supply chain logistic service gas station interface
562.361
#178

Modeling and simulating the socio-ecological system of the rivers of South Korea.

This time we started with a powerful hypothesis developed by a group of researchers from South Korea ... Read more
This time we started with a powerful hypothesis developed by a group of researchers from South Korea, to intervene an ecosystem of complex rivers in their country, on which depends the sustainable development of their community, in this hypothesis the behavior of four sectors is related. Connect the algae growth regulation service, with the care of the environment, the health of the ecosystem, the wetlands and the sandy areas, the population dynamics of the fish, the fish production, the animals and the vegetation that develops in that ecosystem, which also favors. the spiritual and cultural development of the people, its amusement parks for visitors, and the improvement of the aesthetic value of the area, and the dredging and maintenance of its rivers, and better manages the maintenance and construction of dams, the management of the floods and the level of groundwater in terms of balance and redundancy, water management for water for human consumption, water for industrial development and the use of resources. Fertilizers for their watermelon, garlic and onion crops, such as You can see, a powerful and complex history of the real world, perhaps they can also be seen as a national security problem, for which social science will have to be applied for the development of policies. that shed light on the path of long-term sustainability.
sim226 runs
system dynamics Rivers ecosystem environment socio-ecological system and public policy.
555.515
#179

macrolab

macrolab
sim2183 runs
551.74
#180

Supply Chain Dynamics

Use this model to explore the implications of supplier, producer, and consumer attributes on overall ... Read more
Use this model to explore the implications of supplier, producer, and consumer attributes on overall supply chain performance.
sim387 runs, 173 downloads
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Supply Chain inventory main chain reengineering
551.353
#181

An Abundance of Hops

Is the hops imbalance in the craft beer maket a cause for concern for the industry?
sim383 runs, 45 downloads
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Supply chain hops beer surplus shortage
545.672
#182

Spread of Disease

A simple SIR model is examined using the Hayward/Boswell Loop Impact Method.
sim353 runs, 101 downloads
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SIR Disease Infection Loop dominance loop impact
537.393
#183

Tick Tock: The Biological Clock and Circadian Rhythm

Explore gene expression of the transcriptional-translational feedback loop (TTFL) of the mouse circa ... Read more
Explore gene expression of the transcriptional-translational feedback loop (TTFL) of the mouse circadian rhythm.
sim825 runs
circadian clock feedback loop
531.104
#184

Tolerance-Nicotine- Hypothetical Antagonist

Tolerance may be defined as a process that results in a reduction in the response to a specific drug ... Read more
Tolerance may be defined as a process that results in a reduction in the response to a specific drug concentration following repeated drug exposure. One model for tolerance assumes that the drug produces a hypothetical metabolite that opposes its action.
sim661 runs, 11 downloads
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Tolerance Nicotine Hypothetical Antagonist
517.42
#185

Model 15. DDI 3 Reversisble Enzyme Inhibition: Midazolam Fluconazole

This model demonstrates the characteristics of reversible enzyme inhibition using fluconazole's inhi ... Read more
This model demonstrates the characteristics of reversible enzyme inhibition using fluconazole's inhibition of midazolam as an example.
sim333 runs
Reversible inhibition Competitive inhibition Midazolam Fluconazole Enzyme inhibition
517.228
#186

SAVi

sim2471 runs
516.5
#187

Pierce County Homeless Response Model

sim2122 runs
513.12
#188

COVID-19 Economy Model

Our latest Story of the Month explores the economic cost of the COVID-19 stay-at-home orders in the ... Read more
Our latest Story of the Month explores the economic cost of the COVID-19 stay-at-home orders in the United States. Are there policies that can help mitigate these costs? Do the provisions of the CARES Act have a significant effect on the economic outcomes? Find out in our new simulation.
sim1565 runs
Business Economics Education COVID-19 coronavirus
512.495
#189

Dodds Stella Modeling

a SICK model, YEET!
model555 downloads
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Swag Stella Artois Model Scott
508.795
#190

Energy budget V3

sim1367 runs
Environment Ecology
501.343
#191

Urgent Care Hub Workforce Simulator

Urgent Care Hub Workforce Simulator
sim265 runs
Workforce Planning Urgent Care Systems Modelling Whole Systems
498.55
#192

Climate change

This interactive learning environment gives a short explanation of climate change, and teach a surpr ... Read more
This interactive learning environment gives a short explanation of climate change, and teach a surprising insight about policy making.
sim507 runs
Environment Science Education climate change wait and see
490.304
#193

Bricks to Clicks

Experience the dynamics of making a business shift from traditional to e-commerce. Simulate differen ... Read more
Experience the dynamics of making a business shift from traditional to e-commerce. Simulate different scenarios for how you’ll allocate spending on marketing versus infrastructure. You will see one of the more common dynamics in making a business shift, what Systems Thinkers refer to as the "worse before better" dynamic. If initial investments are made in the infrastructure quality rather than in marketing, total customers will actually fall for awhile. But if increasing amounts are spent on marketing (once the infrastructure is in place) then total customers will begin to explode. And the transition becomes successful!
sim340 runs, 112 downloads
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retail strategy iThink
484.84
#194

Population

Sample population model with graph
model686 downloads
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beginner sample population model
481.351
#195

Diagrama causal innovacion

by Randiel
diagrama para representar el ciclo de innovacion
diagram523 downloads
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innovacion empresa ciclo smart planeamiento
479.124
#196

Human Ecological Systems (HES)

The purpose of this model is to (1) demonstrate a way to represent human development that includes i ... Read more
The purpose of this model is to (1) demonstrate a way to represent human development that includes individual resources, social networks, and spatial relationships within a single model of a formal feedback theory of development, (2) provide an approach to theory development that begins with a simple model and gradually includes more complex facets of social reality (e.g., social networks, location), and (3) illustrate its application to formally testing and comparing a theory over a wider range of assumptions that can inform the design of data collection and analysis to more accurately reflect the dynamics of human development and outcomes. The approach has a wide range of possible applications in theory development and community intervention design, research, and evaluation. Examples include school-based and community based positive youth development interventions, drug use/addiction and treatment in rural settings, community responses to domestic violence, neighborhood effects and interventions, homelessness, supports for ex-offenders released from prison or jail, and health inequities. Version 1.0 focuses on mainly working out a simple example of interactions between social networks and spatial relationships. The model (right) represents a formal theory of how people will move to be close to their nearest friend. Since friends are determined by a social network where people have different sets of friends, and people are in different locations, movement will depend on an interaction between each individual’s social network, the location of their friends, the distance to their friends, and identifying their nearest friend and comparing one’s present location to the location of one’s nearest friend. The model implements this with a random social network for 100 individuals randomly distributed in 100m by 100m coordinate space.
sim163 runs
human development social theory methodology social networks spatial relationships
478.675
#197

Tolerance- Precursor Pool Model

Tolerance may be defined as a process that results in a reduction in the response to a specific drug ... Read more
Tolerance may be defined as a process that results in a reduction in the response to a specific drug concentration following repeated drug exposure. Tolerance could occur if an endogenous compound that plays an essential role in the response chain becomes depleted during response. This model assumes the drug stimulates the production of a response variable which becomes then becomes depleted.
sim375 runs, 7 downloads
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Tolerance Pharmacodynamic precurosr pool depletion model
477.945
#198

Limited Enthusiasm Model of Church Growth

A model of the growth of the Christian Church in periods of religious revival. The growth mechanism ... Read more
A model of the growth of the Christian Church in periods of religious revival. The growth mechanism is similar to the spread of an infectious disease.
sim325 runs, 36 downloads
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Church growth Revival Religion Epidemiology Enthusiasts
466.96
#199

CoSimPol

by Shamim
CoSimPol is a Covid-19 Simulator for policy makers, to be able to explore the impacts of Covid-19 in ... Read more
CoSimPol is a Covid-19 Simulator for policy makers, to be able to explore the impacts of Covid-19 including hospitalisation, death rates, infection spread etc. It also has various mitigation mechnsims such as lockdowns and social distancing. The user is able to calibrate for any country or local context and has flexibility to change many of the underlying assumptions on the model to check validity for a given context.
sim321 runs
Covid-19 Lockdowns Social Distance Corona Virus Hospitalisation
458.454
#200

Sustainable Shrimping

This Learning Environment should help you understand some basic population dynamics and their releva ... Read more
This Learning Environment should help you understand some basic population dynamics and their relevance to policy development for sustainable shrimping practices. While the specific context is shrimping, the concepts learned should be transferable to other harvesting situations (fishing, hunting, tree farming, etc.)
sim391 runs, 76 downloads
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population dynamics shrimp harvesting
457.262
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Sim App (Sim)

An interface that allows users to interact with a model.

Image of a sim

Sim apps allow users to interact with a model using buttons, sliders, knobs, tables, graphs, and storytelling. These interactions help users understand how parts of a system interact.

Interfaces are created by model authors in the Stella desktop software and can be uploaded to the isee Exchange.

Model

A diagram that represents how elements in a system influence one another.

Image of a model

Models are mathematical representations of how elements in a system are connected and interact (e.g., ecosystems, organizations, supply chains). When running models on the Exchange, results can be viewed in output devices like graphs and tables.

Models appear in the isee Exchange directory when authors upload them from the Stella® desktop software or create them with Stella Online™.

Causal Loop Diagram (CLD)

A map that represents the feedback structure of a system.

Image of a CLD

CLDs are high-level maps that represents the feedback structure of a system and easily communicate the essence of a model. They appear in the isee Exchange when authors upload them from the Stella desktop software or create them with Stella Online™.