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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We found 200 items
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#1

Lactase Enzyme Simulation with Data Analysis

by Jon Darkow
sim ⋮ 9,880,946 runs
1147678.6
#2

Enzyme Diversity: Enzymes, Products, and Substrates

by Jon Darkow
sim ⋮ 909,672 runs
enzymes substrates products DNA trypsin
761496.4
#3

Lactase with Variable Sample Sizes

by Jon Darkow
Arrayed Lactase Model
sim ⋮ 718,485 runs
Lactase array sample size biology
439245.6
#4

Predator-Prey-LevelA

by Creative Learning Exchange
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.
sim ⋮ 277,597 runs, 342 downloads
Download Model
ecosystem population predator prey oscillation
330272.72
#5

Photosynthesis Model

by Jon Darkow
sim ⋮ 1,917,892 runs
145548.4
#6

Information Processing and Neurophysiology Model

by Jon Darkow
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.
sim ⋮ 216,881 runs
infromation processing neurophysiology biology
115407.23
#7

COVID-19 Simulator

by isee systems
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.
sim ⋮ 112,811 runs
Biology Science Education COVID-19 Coronavirus
98527.94
#8

Apterous Genetics

by Jon Darkow
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?
sim ⋮ 270,944 runs
Genetics
87826.59
#9

Cellular Respiration Accounting Model

by Jon Darkow
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.
sim ⋮ 582,212 runs
cellular respiration aerobic respiration ATP biology
83346.75
#10

Growth Factors, Cyclins, and Cancer

by Jon Darkow
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.
sim ⋮ 264,983 runs
growth factors cyclins cell cycle cancer
70925.766
#11

Vacation

by isee systems
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?
sim ⋮ 31,198 runs, 727 downloads
Download Model
Vacation burnout stress productivity workload
64553.984
#12

Lactose Operon: An Inducible System

by Jon Darkow
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.
sim ⋮ 130,523 runs
Inhibition negative feedback biology lactose operon
55977.305
#13

Zombie Apocalypse

by isee systems
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!
sim ⋮ 19,889 runs, 744 downloads
Download Model
Systems Thinking zombies epidemic disease susceptible
46140.863
#14

College Loans

by isee systems
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.
sim ⋮ 26,310 runs, 969 downloads
Download Model
Student loans loans college interest repayment
45883.24
#15

Neurophysiology and Neurotoxicity

by Jon Darkow
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.
sim ⋮ 46,458 runs
Neurophysiology toxins sarin VX TTX
45152.87
#16

Evolution and Natural Selection

by Jon Darkow
sim ⋮ 299,906 runs
44478.08
#17

Oral Absorption

by Sara Rosenbaum
This model is based on first order absoprtion in a 1-compartment model
sim ⋮ 44,032 runs, 120 downloads
Download Model
Drug Absoprtion Bioavailability Bioequivalence
43909.707
#18

Intravenous Infusion

by Sara Rosenbaum
This model demonstrates the pharmacokinetic characteristics of constant continuous drug administrati ... Read more
This model demonstrates the pharmacokinetic characteristics of constant continuous drug administration.
sim ⋮ 21,910 runs, 79 downloads
Download Model
drug pharmacokinetics intravenous infusion zero order input constant continuous drug administration
43085.52
#19

Model 2. Drug Transporters

by Sara Rosenbaum
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
sim ⋮ 46,638 runs
drug transporters efflux uptake drug absorption
42870.438
#20

Enzyme Diversity

by Jon Darkow
sim ⋮ 421,422 runs
enzyme biology substrate pepsin indicators
42439.12
#21

Photosynthesis with Variable Sample Sizes

by Jon Darkow
Sample sizes of Photosynthesis stocks in an array
sim ⋮ 134,426 runs, 100 downloads
Download Model
34917.33
#22

Oxytocin and Child Birth

by Jon Darkow
sim ⋮ 207,614 runs
33194.6
#23

Population dynamics of white footed mouse

by Jon Darkow
sim ⋮ 905,171 runs
32322.82
#24

Mulitple Bolus Injections Pharmacokinetics

by Sara Rosenbaum
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.
sim ⋮ 17,259 runs, 68 downloads
Download Model
drug pharmacokinetics multiple doses multiple intravenous bolus injections
29649.393
#25

Evolution of Antibiotic Resistance Simulation

by Jon Darkow
Evolution of Antibiotic Resistance Simulation. This model tracks the accumulation of 40 colonies of ... Read more
Evolution of Antibiotic Resistance Simulation. This model tracks the accumulation of 40 colonies of bacteria. The main purpose of the model is to show that new adaptations are not caused by an environmental factor, like antibiotics. Rather, new adaptations are the selection of available variations. In this model you can increase variations by increasing the UV dose. The UV dose increases the mutation rate with a Monte Carlo function.
sim ⋮ 130,900 runs
Biology Science Ecology Education
29567.395
#26

Cellular Respiration Inquiry

by Jon Darkow
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.
sim ⋮ 93,656 runs
metabolism respriation ATP biology
27849.754
#27

Lac Operon with Monod Bump

by Jon Darkow
sim ⋮ 176,549 runs
Lac Operon Gene Regulation mRNA
26653.72
#28

Genotyping with Electrophoresis

by Jon Darkow
sim ⋮ 39,591 runs
biology inheritance DNA restriction enzyme
25722.018
#29

Predator-Prey-LevelC

by Creative Learning Exchange
sim ⋮ 31,504 runs, 69 downloads
Download Model
ecosystem predator prey oscillation balance
25008.414
#30

Photosynthesis Simulation with Variance

by Jon Darkow
sim ⋮ 208,331 runs
24298.7
#31

Multiple Oral Doses Pharmacokinetics

by Sara Rosenbaum
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.
sim ⋮ 14,041 runs, 64 downloads
Download Model
multiple oral doses interactive pharmacokinetics drug bioavailability
23620.355
#32

Limiting Nutrients in Aquatic Ecosystems

by Jon Darkow
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.
sim ⋮ 98,595 runs
limiting nutrients ecosystem biology logistic growth
22352.209
#33

iSDG Tanzania

by Millennium Institute
sim ⋮ 32,030 runs, 1 download
SDG policy integration coherence simulation
22059.113
#34

Guppy Evolution

by Jon Darkow
sim ⋮ 147,591 runs
evolution biology genes
21897.38
#35

2019 Step1

by Ichie Hara
Step1
sim ⋮ 36,370 runs
intravenous oral theophylline
21287.564
#36

Administration routes

by Ichie Hara
observe three type of plasma concentration curve, and combine three of them
sim ⋮ 10,826 runs
Pharmacokinetics intra venous bolus div p.o.
21066.379
#37

Evolution of LAP Allele in Mussels

by Jon Darkow
sim ⋮ 70,364 runs
Evolution Natural Selection Cline
18359.453
#38

SIR COVID-19 Coronavirus Simulation

by Jon Darkow
sim ⋮ 17,439 runs
Environment Biology Science Education SIR
18349.06
#39

Lotka-Volterra Predator-Prey Model

by Jon Darkow
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.
sim ⋮ 208,677 runs
negative feedback loop Lotka-Volterra homeostasis predator-prey
18095.824
#40

Route21

by Ichie Hara
Administration routes
sim ⋮ 30,827 runs
Biology Science Education pharmacokinetics simulation
17955.232
#41

Automation

by isee systems
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!
sim ⋮ 7,286 runs, 467 downloads
Download Model
Automation job loss AI artificial intelligence labor force
17948.607
#42

Closed Loop

by Christopher Quick
Mininimal closed-loop model of the cardiovascular system
sim ⋮ 92,602 runs
16728.48
#43

Pharmacokinetics: An IV Injection on a Two Compartment Model

by Sara Rosenbaum
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
sim ⋮ 18,110 runs, 61 downloads
Download Model
drug pharmacokinetics IV two compartment model
16694.45
#44

White-Eyed Genetics

by Jon Darkow
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?
sim ⋮ 146,528 runs
Genetics
15157.406
#45

COVID-19 Model

by isee systems
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.
model ⋮ 11,115 downloads
Download Model
Biology Science Education COVID-19 Corona Virus
13764.885
#46

HPV with Influenza A Humoral Immunity

by Jon Darkow
Immune response of HPV
sim ⋮ 24,004 runs
HPV antibodies biology Immunity
13624.208
#47

Nonlinear Pharmacokinetics and Phenytoin

by Sara Rosenbaum
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.
sim ⋮ 7,481 runs, 49 downloads
Download Model
nonlinear pharmacokinetics capacity limited elimination drug phenytoin
13607.894
#48

Diffusion of a Spherical Cell

by Jon Darkow
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.
sim ⋮ 131,191 runs
diffusion surface area volume radius
12697.543
#49

Multiple Intermittent Infusions Pharmacokinetics

by Sara Rosenbaum
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.
sim ⋮ 6,146 runs, 38 downloads
Download Model
Multiple intermittent infusions aminoglycoside infusion drug interactive pharmacokinetics
12304.316
#50

Transformation Simulation

by Jon Darkow
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.
sim ⋮ 119,417 runs
transformation DNA biology
11900.882
#51

Dosing regimen for renal failure

by Ichie Hara
Dosing regimen for renal failure
sim ⋮ 15,583 runs
Biology Science Education pharmacokinetics simulation
11675.799
#52

Thyroid Hormone - Negative Feedback

by Jon Darkow
sim ⋮ 63,467 runs
negative feedback thyroid hormone metabolism biology
11474.974
#53

Predator-prey-LevelB

by Creative Learning Exchange
Level B: Wild Things: Interacting Populations This lesson allows students to explore the interactio ... Read more
Level B: Wild Things: Interacting Populations This lesson allows students to explore the interactions of two animal populations (predator and prey) within an ecosystem. Their populations can rise and fall (oscillate) over time as they interact and impact one another.
sim ⋮ 11,675 runs, 33 downloads
Download Model
ecosystem predator prey oscillation
11075.274
#54

Sigmoidal Emax Model of Drug Response

by Sara Rosenbaum
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.
sim ⋮ 9,511 runs, 60 downloads
Download Model
Pharmacodynamic Drug Sigmoidal Emax Emax
10624.545
#55

Tolerance-Nicotine- Hypothetical Antagonist

by Sara Rosenbaum
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.
sim ⋮ 10,226 runs, 28 downloads
Download Model
Tolerance Nicotine Hypothetical Antagonist
10549.93
#56

Recombination and Gene Linkage

by Jon Darkow
sim ⋮ 111,408 runs
10396.5
#57

H1N1 Flu Outbreak

by isee systems
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.
sim ⋮ 5,576 runs, 325 downloads
Download Model
Environment Biology Education Flu outbreak
10338.538
#58

Populations-LevelC

by Creative Learning Exchange
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.
sim ⋮ 12,537 runs, 77 downloads
Download Model
populations logistic
10015.765
#59

Understanding the Measles Outbreak

by isee systems
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.
sim ⋮ 5,340 runs, 376 downloads
Download Model
Measles vaccine infectious disease quarantine WOM
9927.66
#60

Understanding Restrictive and Nonrestrictive Hepatic Clearance

by Sara Rosenbaum
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.
sim ⋮ 7,571 runs
drug metabolism clearance elimination restrictive clearance
9844.314
#61

Water Potential and Osmosis

by Jon Darkow
Factors that affect the flow across a semi-permeable membrane.
sim ⋮ 338,179 runs
9492.25
#62

Pharmacokinetics: An IV Injection in a 1-Compartment Model

by Sara Rosenbaum
sim ⋮ 34,498 runs, 97 downloads
Download Model
8904.74
#63

Temperature Control

by isee systems
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.
sim ⋮ 4,757 runs, 410 downloads
Download Model
Temperature proportional integral controller Newton's law heat pump
8261.026
#64

Choosing the Future

by Peter Victor
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
sim ⋮ 5,566 runs
economic growth post-growth no growth sustainable prosperity environment
8187.2695
#65

Model 1. Introduction to PK and PD

by Sara Rosenbaum
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
sim ⋮ 61,510 runs
Pharmacokinetics Pharmacodynamics Therapeutic Range
7962.84
#66

Housing Supply and Demand

by isee systems
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?
sim ⋮ 3,924 runs, 676 downloads
Download Model
Modules finance debt economics housing demand
7827.86
#67

Predator-prey-biomass-LevelA

by Creative Learning Exchange
Predator/Prey/Biomass Level A: All Together Now: Predator, Prey and Plants This lesson allows st ... Read more
Predator/Prey/Biomass Level A: All Together Now: Predator, Prey and Plants This lesson allows students to explore the interactions of two animal populations (wolves and moose) and plants within an ecosystem. The populations and the plants rise and fall (oscillate) over time as they interact and impact one another.
sim ⋮ 10,372 runs, 39 downloads
Download Model
ecosystems oscillation
7754.259
#68

The Power of The Missing Middle

by isee systems
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.
sim ⋮ 2,732 runs, 267 downloads
Download Model
Trump missing middle vicious cycle storytelling manufacturing jobs
7552.051
#69

Sustainable Shrimping

by isee systems
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.)
sim ⋮ 6,672 runs, 234 downloads
Download Model
population dynamics shrimp harvesting
6962.799
#70

interval

by Ichie Hara
dosing interval
sim ⋮ 11,388 runs
Biology Science Education pharmacokinetics simulation
6417.2085
#71

Circadian Clock in the Mouse

by Jon Darkow
Transcriptional Translational Feedback Loop in the Mouse
sim ⋮ 26,999 runs
Mouse Circadian Clock
6287.12
#72

The dynamics of photosynthesis - variable sample size

by Jon Darkow
The dynamics of photosynthesis - variable sample size
sim ⋮ 89,920 runs
photosynthesis sample size biology
6107.4043
#73

Predator-Prey-Biomass-LevelC

by Creative Learning Exchange
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.
sim ⋮ 4,571 runs, 84 downloads
Download Model
science ecosystem oscillation predator prey
6101.051
#74

Phenology of the Karner Blue Butterfly

by Jon Darkow
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.
sim ⋮ 10,885 runs
asynchrony timing phenology climate change butterfly
6075.1133
#75

Tryptophan Operon: A repressible system

by Jon Darkow
sim ⋮ 76,641 runs
6033.44
#76

Dosing regimen for renal failure

by Ichie Hara
compare plasma concentration in renal failure, plan the dosing regimen in renal failure
sim ⋮ 3,584 runs
Pharmacokinetics creatinine clearance Scr Clcr aminoglycoside
5986.255
#77

Dairy Cows

by isee systems
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.
model ⋮ 4,743 downloads
Download Model
Systems in Focus agriculture cows dairy
5816.717
#78

Populations-LevelA

by Creative Learning Exchange
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).
sim ⋮ 11,941 runs, 67 downloads
Download Model
population ecology
5739.87
#79

Guns At School

by isee systems
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.
sim ⋮ 7,753 runs
Guns Schools Public Policy Violence Bullying
5663.236
#80

Simple Genetics

by Jon Darkow
sim ⋮ 110,555 runs
5645.78
#81

Headcount Strategy

by isee systems
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.
sim ⋮ 2,380 runs, 376 downloads
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Headcount employees growth manager consultant
5644.013
#82

Irreversible Drug Effects - Proton Pump Inhibitors

by Sara Rosenbaum
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).
sim ⋮ 2,445 runs, 21 downloads
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Pharmacodynamic Irreversible Drug Effects Proton Pump Inhibitors PPI Response Model
5077.0366
#83

Pattern with recessive single band

by Jon Darkow
sim ⋮ 83,242 runs
genetics
4556.12
#84

Steady State in Freshwater Ecosystems

by Jon Darkow
sim ⋮ 31,630 runs
4370.22
#85

Animal Temperature

by isee systems
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
sim ⋮ 1,767 runs, 147 downloads
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Thermodynamcis adaptation poiklothermic homeothermic Warm-blooded
4355.882
#86

Limits to Growth Archetype

by John Hayward
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.
sim ⋮ 2,118 runs, 206 downloads
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Business Loop Dominance Limits to Growth Shifting loop dominance Urban Dyanmics
4303.582
#87

COVID-19: Vertical Isolation in Brazil

by isee systems
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).
sim ⋮ 4,517 runs
Biology Science Education COVID-19 coronavirus
4261.6685
#88

Business Cycle Dynamics

by isee systems
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.
sim ⋮ 1,724 runs, 523 downloads
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supply chain semiconductor oscillation. production planning capacity management
4059.6824
#89

Urban Business Expansion

by John Hayward
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.
sim ⋮ 2,002 runs, 129 downloads
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Loop Dominance Limits to Growth Shifting loop dominance Urban Dyanmics Loop Impact
3997.433
#90

Macromodel

by Pervin Dadashova
Model for the public policy testing
sim ⋮ 15,155 runs, 58 downloads
Download Model
3944.91
#91

Change the dosing interval

by Ichie Hara
interval & dosing, regularly or irregularly
sim ⋮ 2,922 runs
Pharmacokinetics dosing interval irregular interval TMU Hara
3880.835
#92

Extended Agrarian Society (from Dynamic Systems)

by Paul Fisher
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.
model ⋮ 1,672 downloads
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population agriculture industrialization climate ice sheet
3628.356
#93

Pulmonary Edema

by Christopher Quick
This model predicts collection of fluid in the lungs.
sim ⋮ 13,987 runs
3620.69
#94

Basic Stella Builtins Library

by UiB MINDS
© Will Noyes 2020 This is an educational tool to learn about the commonly used builtin formulas in ... Read more
© Will Noyes 2020 This is an educational tool to learn about the commonly used builtin formulas in Stella. For each formula there is a basic description, a model representation that allows you to control the different inputs, and one or two output graphs that show the result of that formula. If you would like more information on any of these builtins or on any that are not demonstrated here, remember that you can always consult Stella Help.
model ⋮ 2,479 downloads
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Education Stella Builtin teaching UiB
3608.1074
#95

Transformation Experiment with Controls

by Jon Darkow
Simulation allows users to test the bacterial transformation principle discovered by Frederick Griff ... Read more
Simulation allows users to test the bacterial transformation principle discovered by Frederick Griffith.
sim ⋮ 25,377 runs
Biology Science Education transformation DNA
3532.68
#96

Thinking About Drinking

by Creative Learning Exchange
What happens WHEN someone you know drinks? That depends, on the amount of alcohol consumed, the time ... Read more
What happens WHEN someone you know drinks? That depends, on the amount of alcohol consumed, the timeframe, along with a number of personal characteristics. Indeed, the level of alcohol which builds up in a person's bloodstream can vary enormously.
sim ⋮ 2,378 runs, 50 downloads
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Biology Science Education alcohol teen drinking
3511.666
#97

Humanitarian Aid

by isee systems
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
sim ⋮ 1,988 runs, 250 downloads
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Disaster relieft Water Mark Heffernan George McDonnel scenarios
3324.7932
#98

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.
model ⋮ 1,163 downloads
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Financial instability Karl Marx Richard Goodwin Hyman Minsky Steve Keen
3273.14
#99

Biomass Accumulation Model

by GLOBE Program
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).
sim ⋮ 4,294 runs
biomass biomass accumulation carbon cycle globe npp
3226.2607
#100

COVID-19 Model By Age

by isee systems
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.
model ⋮ 2,786 downloads
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Biology Science Education COVID-19 Coronavirus
3191.9666
#101

Airport Runway Capacity

by isee systems
Examine the implications of an increasing number of landing airplanes on a fixed capacity runway.
sim ⋮ 1,486 runs, 387 downloads
Download Model
Reengineering discrete modeling queues iThink process improvement
3091.0073
#102

HPV and Adaptive Immune Response

by Jon Darkow
sim ⋮ 9,241 runs
HPV Antibodies feedback loops vaccine
3043.92
#103

Evolution with Heterozygous Advantage

by Jon Darkow
Evolution of Populations: Genetic Drift, Natural Selection, and Mutations
sim ⋮ 7,647 runs
evolution natural selection genetic drift
2981.2375
#104

PEOPLE-EXPRESS

by Khalid+Saeed
A SIMPLIFIED VERSION OF PEOPLE EXPRESS GAME FOR CLASSROOM OR GROUP USE
sim ⋮ 8,494 runs
Business Economics Education
2980.1
#105

Simple Global Carbon Cycle Model

by GLOBE Program
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).
sim ⋮ 10,628 runs
carbon cycle carbon global globe simple
2975.8347
#106

2019 Step2

by Ichie Hara
dosing interval
sim ⋮ 9,368 runs
regular irregular
2971.35
#107

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

by Sara Rosenbaum
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
sim ⋮ 2,386 runs, 35 downloads
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Drug Hysteresis Effect Compartment Pharmacodynamics
2887.088
#108

Energy Demand Lab

by isee systems
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.
sim ⋮ 1,342 runs, 457 downloads
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Energy residential industrial agricultural energy usage
2842.248
#109

Integrated Population System

by Paul Fisher
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.
model ⋮ 1,138 downloads
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population agriculture industrialization climate ice sheet
2781.442
#110

Stella Architect B.M. Sample

by Armando Izquierdo
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".
sim ⋮ 621 runs, 140 downloads
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Stella Architect Business Canvas Modelos de Negocios Alex Osterwalder Simulación
2752.8826
#111

traffic congestion

by isee systems
Explores the dynamics of road use and road construction.
model ⋮ 3,927 downloads
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traffic urban planning congestion
2562.732
#112

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

by Michael L Deaton
sim ⋮ 3,632 runs
Environment Biology Business Technology Science
2508.72
#113

Catastrophic Regime Change in Aquatic Ecosystems

by Jon Darkow
sim ⋮ 88,377 runs
Ecology
2476.12
#114

Global Carbon Cycle Model with Feedbacks

by GLOBE Program
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)
sim ⋮ 5,776 runs
carbon carbon cycle global globe feedbacks
2446.44
#115

Spring-LevelB

by Creative Learning Exchange
Level B: Exploring Springs: A Little Bounce in the World Students explore a simple spring simulat ... Read more
Level B: Exploring Springs: A Little Bounce in the World Students explore a simple spring simulation to see how springs behave, given different characteristics. Students can change the springiness (spring constant), the resistance, a mass at the end of the spring, and the amount of push or pull.
sim ⋮ 4,594 runs, 13 downloads
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Science
2267.4517
#116

Supply Chain Dynamics

by isee systems
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.
sim ⋮ 1,730 runs, 503 downloads
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Supply Chain inventory main chain reengineering
2255.6787
#117

Limited Enthusiasm Model of Church Growth

by John Hayward
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.
sim ⋮ 1,482 runs, 55 downloads
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Church growth Revival Religion Epidemiology Enthusiasts
2213.12
#118

Indirect Effect Model 1

by Sara Rosenbaum
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.
sim ⋮ 1,986 runs, 30 downloads
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indirect effect warfarin inhibition of kin
2130.5417
#119

Predator-prey-biomass-LevelB

by Creative Learning Exchange
Predator/Prey/Biomass Level B: Circles of Interaction: Predator, Prey and Plants This lesson explo ... Read more
Predator/Prey/Biomass Level B: Circles of Interaction: Predator, Prey and Plants This lesson explores predator (wolf), prey (moose), and food (plants) within an ecosystem. Students role-play being a wildlife manager who is doing "on the job" training. The manager controls hunting of prey populations and killing of predators. The default simulation behavior for prey, predators, and food is oscillation.
sim ⋮ 2,960 runs, 19 downloads
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oscillation ecosystem
2076.0894
#120

Dynaville

by Valerie Gacogne
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.
sim ⋮ 1,209 runs
attractivité territoire habitants démographie politique de logements déplacements
2071.3733
#121

Systems In Focus: Environment

by isee systems
One of the greatest environmental challenges we face is how to do more with less: Less raw materials ... Read more
One of the greatest environmental challenges we face is how to do more with less: Less raw materials, less pollution, less damage to the environment. This model shows the life-cycle assessment for the aggregate products manufactured and consumed in a firm, an industry, a region, a nation, or the world. It focuses on solid waste, though it would be easy to add air or water pollution generated and energy consumed at each stage.
model ⋮ 1,441 downloads
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Environment Ecology Renewable Resources Raw Material
1988.5156
#122

Extinction Vortex

by Jon Darkow
sim ⋮ 46,297 runs
1888.52
#123

BacterialGrowth

by Daniel Edward McMahon
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
model ⋮ 941 downloads
Download Model
1867.183
#124

Process with Complete Quality Control Feedback Mechanisms

by Anthony Dowidowicz
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.
model ⋮ 654 downloads
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quality quality control quality based payments us healthcare policy rate dependent quality
1838.282
#125

Tesing Unknown Enzymes

by Jon Darkow
sim ⋮ 212,610 runs
enzymes
1804.54
#126

COVIDGlobal

by Hazhir Rahmandad
Projections for COVID-19 pandemic across the globe
sim ⋮ 5,127 runs
COVID-19 Pandemic
1790.66
#127

Transit Compartment of Drug Action

by Sara Rosenbaum
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.
sim ⋮ 963 runs, 35 downloads
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Pharmacodynamics Transit compartment Delayed drug action
1789.25
#128

Systems In Focus: Water

by isee systems
A lot is happening behind the scenes to create this picturesque vista. Rainfall on land creates runo ... Read more
A lot is happening behind the scenes to create this picturesque vista. Rainfall on land creates runoff and therefore stream flow. Some of this runoff is absorbed into the soil. Some of that flows beneath the ground to the stream and some returns to the air through evapotranspiration. Another part of it percolates further down through the soil layers to become part of the groundwater, which provides a base level flow for the stream. Using Stella Professional, we are able to draw a map that corresponds closely to the physical world and then simulate that map to see what happens. This both increases our understanding of how this system works and allows us to experiment with different policies that might lead to alternate, more desirable outcomes.
model ⋮ 1,592 downloads
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Environment Ecology
1770.3627
#129

Beta Cell Simulation - Split story

by Jon Darkow
sim ⋮ 53,938 runs
1761.38
#130

Building a Model of Church Growth Using System Dynamics

by John Hayward
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.
sim ⋮ 1,029 runs, 25 downloads
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church growth word of mouth enthusiasts model construction Hayward
1755.1067
#131

System Dynamics of Carbon Budget

by Jon Darkow
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)
sim ⋮ 15,507 runs
system dynamics carbon climate
1704.2217
#132

Story of the Month Reissue: Deficit

by isee systems
Examines the often-confused concepts of deficits versus surpluses and tax cuts versus tax rebates.
sim ⋮ 907 runs, 102 downloads
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tax cuts tax rebates deficit surplus social security
1696.102
#133

macrolab2017

by David Wheat
sim ⋮ 6,620 runs
1682.86
#134

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.
sim ⋮ 3,694 runs
health systems shifting boat
1674.28
#135

Abastecimento de Água

by Mariana Lago
Demanda de água gera novos investimentos em infraestrutura de abastecimento
diagram ⋮ 1,664 downloads
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demanda de água abastecimento urbano investimentos
1633.09
#136

COVID-19 Economy

by isee systems
This models the economic impacts of an extended shutdown due to the coronavirus pandemic and explore ... Read more
This models the economic impacts of an extended shutdown due to the coronavirus pandemic and explore the policies adopted by the United States to mitigate these effects.
model ⋮ 1,529 downloads
Download Model
Business Science Economics COVID-19 coronavirus
1601.791
#137

Tolerance- Precursor Pool Model

by Sara Rosenbaum
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.
sim ⋮ 1,136 runs, 14 downloads
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Tolerance Pharmacodynamic precurosr pool depletion model
1589.3
#138

Molecules

by Jim Hines
Molecules of System Dynamics Structure: Small generic structures useful in building simulation model ... Read more
Molecules of System Dynamics Structure: Small generic structures useful in building simulation models.
model ⋮ 1,368 downloads
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Molecules models building blocks learning
1586.916
#139

Logistic Growth Model and the Butterfly Effect

by Jon Darkow
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.
sim ⋮ 4,003 runs
logistic growth carrying capacity
1575.0834
#140

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!
sim ⋮ 3,391 runs
Weight loss Health
1546.4166
#141

Campus sexual assault

by Peter Hovmand
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.
sim ⋮ 1,434 runs, 45 downloads
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campus sexual assault community norms
1514.7633
#142

The Laundry Detergent Game

by Billy Schoenberg
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?
sim ⋮ 952 runs, 108 downloads
Download Model
system dynamics bass diffusion model marketing
1497.5266
#143

Supply Chain Management without Forecasting

by isee systems
Accurate demand forecasting is an essential part of most supply chain management algorithms. Yet, s ... Read more
Accurate demand forecasting is an essential part of most supply chain management algorithms. Yet, supply even in the most diligently managed chains can deviate widely from demand. Additionally, any disturbance in demand will often be amplified in a supply chain creating what is known as bullwhip effect. This simulation uses three parsimonious models to demonstrate that supply can be regulated reliably without forecasting demand. The inspiration for these models comes from PID (Proportional, Integral, Derivative) control in engineering controllers that utilize multiple functions of error (discrepancy between goal and actual condition) to regulate a quantity.
sim ⋮ 1,022 runs, 265 downloads
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Business operations management
1496.7506
#144

Bed capacity model

by Whole Systems Partnership
stcs
sim ⋮ 954 runs, 74 downloads
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Bed Capacity Model Whole Systems
1466.632
#145

Educational Outcomes

by Emily Brzozowski
Educational outcomes in relation to resource allocation
model ⋮ 1,346 downloads
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Education resources funding student achievement
1451.24
#146

Carbon Budget Simulator

by Peter Victor
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.
sim ⋮ 1,230 runs
Environment Technology Science Economics
1445.659
#147

Systems In Focus: Energy

by isee systems
Building capacity in alternative energy sectors takes time and large investments. The transition to ... Read more
Building capacity in alternative energy sectors takes time and large investments. The transition to other sources has to be financially feasible, as well as timely to prevent further damage from pollution. How can the mix of electricity generation technology change, based on both cost and pollution? This Systems in Focus model analyses how capacity can be developed in different energy sectors over time.
model ⋮ 1,624 downloads
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Technology Science Energy
1436.384
#148

Evolving Bits

by Jon Darkow
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.
sim ⋮ 1,630 runs
Diversity Selection Evolution Receptor Antigen
1432.19
#149

Resource Allocation

by isee systems
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.
sim ⋮ 1,269 runs, 337 downloads
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human resources headcount
1423.438
#150

Take the Infusion Challenge

by Sara Rosenbaum
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.
sim ⋮ 10,774 runs
Dosing Drug Pharmacokinetics Constant Continuous Input
1406.875
#151

Turchin’s Metaethnic Frontier Theory of Imperial Growth

by John Hayward
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.
sim ⋮ 321 runs, 86 downloads
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Turchin Empire Collapse Collins Geopolitical
1395.8203
#152

SysQ

by Pontifex
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.)
sim ⋮ 682 runs
systems thinking system dynamics sysq resource guide
1387.7723
#153

Salmon Life Cycle Simulator

by Ryan Bellmore
sim ⋮ 1,400 runs
Pacific salmon life cycle modeling water temperature stream flow
1342.3534
#154

Supply Chain: Logistic Service Gas Station

by ernesto lagarda
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
model ⋮ 1,067 downloads
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supply chain logistic service gas station interface
1314.421
#155

SellPhone solo

by Martin Schaffernicht
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)
sim ⋮ 1,131 runs
SellPhone Growth Diffusion Schaffernicht Groesser
1309.6986
#156

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

by Gian Wieck
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.
sim ⋮ 881 runs
lionfish invasion system dynamics caribbean
1288.29
#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
model ⋮ 889 downloads
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learning support scaffold online science
1258.8687
#158

Electric Vehicles in Norway (Model)

by UiB MINDS
© Daria Yermolova & Valentina Orliuk 2020 A model that examines the various factors affecting the el ... Read more
© Daria Yermolova & Valentina Orliuk 2020 A model that examines the various factors affecting the electric car market in Norway, originally built for the course GEO-SD304 at UiB.
model ⋮ 658 downloads
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Environment Business Technology transport electric
1238.304
#159

Physiologically Based Pharmacokinetic Model

by Sara Rosenbaum
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
sim ⋮ 2,443 runs
Drug Pharmacokinetic PBPK Physiologically Based Pharmacokinetic Model
1207.192
#160

GEOSC202 diagenesis lab

by Matthew Fantle
sim ⋮ 3,521 runs, 12 downloads
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Environment Science
1204.2633
#161

Wetland Forestland hydrology

by Sam Probert
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
model ⋮ 1,118 downloads
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Precipitation Evaporation Infiltration Groundwater
1198.1267
#162

Inventory Workforce Model

by John Hayward
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.
sim ⋮ 566 runs, 167 downloads
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Loop Impact Loop Impact Workforce Inventory Control Oscillations
1189.159
#163

Systems In Focus: Conservation

by isee systems
Fishing areas are within the commons, which encourages greater investment in ships when there is dem ... Read more
Fishing areas are within the commons, which encourages greater investment in ships when there is demand. More importantly, we can never really know the population of the given fishery and therefore whether it is in danger of being fished out. This model explores the trade-offs between investing in more ships to catch more fish and the long-term viability of the fishery.
model ⋮ 1,063 downloads
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Environment Business Technology Ecology
1183.766
#164

COVID-19: Vaccinations in the USA

by isee systems
This model explores the vaccination program in the United States and its effort to control the COVID ... Read more
This model explores the vaccination program in the United States and its effort to control the COVID-19 pandemic. It includes vaccine hesitancy, people's behavior in response to perceived risk, and vaccine effectiveness.
sim ⋮ 3,516 runs
Biology Science Education COVID-19 Coronavirus
1182.511
#165

Amalgamated Industries

by isee systems
sim ⋮ 4,327 runs, 236 downloads
Download Model
1175.98
#166

Leg VS Asprin

by Abbey McDonald
ur leg, vs, some asprin
model ⋮ 989 downloads
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leg asprin fight title fight fight for title
1158.1703
#167

Covid19-Epidemie-ModelEducationBase1B

by Eyüp Akçetin
This model was copied from Gigaroff: 1. French (in English in 2.) Modèles pour mieux comprendre la ... Read more
This model was copied from Gigaroff: 1. French (in English in 2.) Modèles pour mieux comprendre la dynamique d'une épidémie et comment les mesures prises permettent d'en atténuer les effets" - Projet interdisciplines Hervé Gigaroff, Lycée "Emile Combes" de Pons 17 (France)-
 • Ceci est le Modèle de base “1.B” pour commencer à mieux comprendre la dynamique d'une épidémie, type CoVid 19, , simplifiée mais tout à fait réaliste… …Avant de voir, avec des modèles suivants, comment les mesures prises permettent d'en atténuer les effets" Pour les “matheux”, fans d’équations différentielles, ce modèle n’est jamais que la mis en forme, selon les lois de le “SYSTÉMIQUE DYNAMIQUE” de ce qui est représenté , en équations différentielles dans cette excellente vidéo: https://www.youtube.com/watch?v=-2tI3MQFqkI&fbclid=IwAR3QdfrTCQPKNUogozNchAlpu0SwTlvQx_fPNaTDjZ1ijdk6wc0snzJc69k Donc ce modèle permet aux “non-matheux” d’aborder cette compréhension… 2 jeux “Épidémie Covid19 #1 et #2” , permettant de vivre (en”pour de semblant”) la dynamique d’une épidémie, vont accompagner ces modèles , qui ne sont que le débriefing de ce qui s’est passé dans ces “jeux”. • Websites récents sur "Epidémies & modélisation" : 1.https://www.youtube.com/watch?v=bM7AOBxqjnE, titré "Cette pandémie, vue depuis 2021" du site "Dirty Biology", 2.https://sciencetonnante.wordpress.com/2020/03/12/epidemie-nuage-radioactif-et-distanciation-sociale/ , titré "Épidémie, nuage radioactif et distanciation sociale", 3.https://medium.com/tomas-pueyo/coronavirus-le-marteau-et-la-danse-bce68d354c0c, titré "Coronavirus, le marteau et la danse". -------------------------------------------------------------------------------------------------------------------- • 2. English: Models for a better understanding of the dynamics of an epidemic and how protective measures make it possible to mitigate the effects "- Interdisciplinary project Hervé Gigaroff, High-school Emile Combes de Pons 17 (France) • Here is Basic model “1.B” to begin to better understand the dynamics of an epidemic, type CoVid 19, in asimplified but completely realistic way… … Before seeing, with the further models, how measures taken can mitigate the effects For the "math minded students”, fans of differential equations, this model is nothing else than the shaping, according to the laws of the "DYNAMIC SYSTEM" of what is represented, in differential equations in this excellent video : https://www.youtube.com/watch?v=-2tI3MQFqkI&fbclid=IwAR3QdfrTCQPKNUogozNchAlpu0SwTlvQx_fPNaTDjZ1ijdk6wc0snzJc69k So this model allows the "non-math minded students" to approach this understanding ... 2 games “Covid19 epidemic # 1 and # 2”, allowing to live (“for pretense”) the dynamics of an epidemic, will accompany these models, which are only the debriefing of what happened in these “games”. • Websites récents sur "Epidémies & modélisation" : 1.https://www.youtube.com/watch?v=bM7AOBxqjnE, titled "This pandemia, seen from 2021" from website "Dirty Biology", 2.https://sciencetonnante.wordpress.com/2020/03/12/epidemie-nuage-radioactif-et-distanciation-sociale/ , titled "Epidemic, nuage radioactive cloud and social distanciation", 3.https://medium.com/@tomaspueyo/coronavirus-the-hammer-and-the-dance-be9337092b56 , titled "Coronavirus, the hammer and the dance".
model ⋮ 257 downloads
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Environment Biology Science Ecology Education
1155.4657
#168

Model 20. DDI Drug-Drug Interactions - Pharmacodynamic

by Sara Rosenbaum
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
model ⋮ 1,123 downloads
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Drug Interactions Pharmacodynamic Partial Agonist
1143.4164
#169

Product Development Simulator

by Billy Schoenberg
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.
sim ⋮ 1,081 runs
product development game simulator bass diffusion marketing
1141.264
#170

Indirect Effect Model 4

by Sara Rosenbaum
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 IV can be used for drugs that stimulate the degradation of the response variable. As a result they decrease the amount of the response variable.
sim ⋮ 738 runs, 11 downloads
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Drug Pharmacodynamics Indirect Effect Model 4 Stimulation of kout
1134.0867
#171

Cash for Clunkers

by isee systems
On July 24th, 2009 the Car Allowance Rebate System (CARS), commonly known as "Cash for Clunkers," be ... Read more
On July 24th, 2009 the Car Allowance Rebate System (CARS), commonly known as "Cash for Clunkers," began processing rebate claims. The $1 billion appropriated for the system was exhausted just SIX days later. This simulation explores an alternative program that is self-sustaining AND reduces automobile emissions. Using a combination of fees and rebates this program can finance itself (no emergency appropriations from Congress), reduce gasoline consumption (putting cash back in consumer's pockets), AND contribute to cleaner air for us all!
sim ⋮ 837 runs, 62 downloads
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Cash Cars freebates policy iThink
1109.7413
#172

Customer-Employee Satisfaction

by isee systems
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.
sim ⋮ 535 runs, 308 downloads
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Customer satisfaction employee satisfaction human resourses
1097.72
#173

SellPhone solo v2

by Martin Schaffernicht
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)
sim ⋮ 6,659 runs
SellPhone Growth dynamics Diffusion Martin Schaffernicht Stefan Groesser
1092.7866
#174

The Wolves of Yellowstone

by isee systems
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.
sim ⋮ 30 runs, 456 downloads
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Keystone species Wolves wolf Trees Aspen
1070.4087
#175

Stella project

by Julianne Bantayan
Simulation showing how cyber attacks have grown in various years.
model ⋮ 939 downloads
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amount of attacks attacks per year increase rate of attacks
1069.625
#176

Fun with Springs-LevelA

by Creative Learning Exchange
This simulation is part of the oscillations series from the Creative Learning Exchange, http://www.c ... Read more
This simulation is part of the oscillations series from the Creative Learning Exchange, http://www.clexchange.org/curriculum/complexsystems/oscillation/default.asp
sim ⋮ 1,531 runs, 11 downloads
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spring physics oscillation
1065.6423
#177

Collins Theory of Geopolitics - Effect of War

by John Hayward
The spread of an empire according to the theory of Randall Collins and equations of Peter Turchin
sim ⋮ 409 runs, 62 downloads
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war empire geopolitics collins turchin
1062.267
#178

Tu Patineta (A) - English Version

by Fabio Ponce
This simulator is based on a case called Tu Patineta (A), written by Dr. Roy Zuñiga, full teacher at ... Read more
This simulator is based on a case called Tu Patineta (A), written by Dr. Roy Zuñiga, full teacher at Incae Business School. It is not intended to offer an accurate solution to the case, but to simulate the possible behaviors of the process considering changes in the input variables described in it.
sim ⋮ 1,297 runs
Business Education Operations
1054.248
#179

UHE1

by Barry Newell
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)
sim ⋮ 3,976 runs
system dynamics basic concepts
1005.258
#180

Service Call Center Dynamics

by isee systems
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.
sim ⋮ 500 runs, 257 downloads
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discrete modeling queues conveyors cycle time
1003.667
#181

Supply and demand model

by Yaroslav Vorobiov
Supply and demand model
sim ⋮ 971 runs, 244 downloads
Download Model
Supply demand model money stella
985.764
#182

Prediction-Wave3-Part1

by Phanuwich Kaewkamjornchai
sim ⋮ 4,202 runs
Health
984.24
#183

Evolution: Grants Finches

by Jon Darkow
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.
sim ⋮ 9,692 runs
evolution biology natural selection
976.6
#184

Diagrama causal innovacion

by Randiel
diagrama para representar el ciclo de innovacion
diagram ⋮ 1,056 downloads
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innovacion empresa ciclo smart planeamiento
963.088
#185

Multiple Retailer Supply Chain

by isee systems
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.
sim ⋮ 304 runs, 356 downloads
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iThink inventory arrays conveyors supply chain
961.564
#186

mse-litsim

by Lorenzo Andrade
Modelo de Simulación de Escenarios MSE-LITSIM
sim ⋮ 910 runs
gestión áreas litorales eutrofización estuarios humedales
957.55
#187

2019 Step3 renew

by Ichie Hara
sim ⋮ 19,277 runs
951.48
#188

Population

by Billy Schoenberg
Sample population model with graph
model ⋮ 1,372 downloads
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beginner sample population model
946.00134
#189

The Shrimp Lab

by Bob Landel
“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.
sim ⋮ 4,304 runs
Environment Biology Business Economics Ecology
945.7813
#190

Gora Model Balanced Scorecard

by Michael L Deaton
sim ⋮ 4,064 runs
945.24
#191

YVSP Neighborhood

by StevePeterson
A neighborhood scale version of the Youth Violence System Project Model
sim ⋮ 4,785 runs
916.29
#192

Sürat ve Alınan Yol

by Emre Göktepe
sim ⋮ 5,100 runs
Education
900
#193

Dodds Stella Modeling

by Henry Dodds
a SICK model, YEET!
model ⋮ 995 downloads
Download Model
Swag Stella Artois Model Scott
895.555
#194

Bricks to Clicks

by isee systems
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!
sim ⋮ 646 runs, 167 downloads
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retail strategy iThink
885.4533
#195

Magallanes ESP

by Martin Schaffernicht
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.
sim ⋮ 546 runs
Magallanes Sobrecrecimiento y colapso Martin Schaffernicht Universidad de Talca
883.0493
#196

SAMDEC

by Benoit Thibodeau
The Stella version of Arctic Mediterranean Double Estuarine Cirulation Box Model
sim ⋮ 1,164 runs, 17 downloads
Download Model
ocean circulation freshwater
875.0867
#197

Childhood Obesity in GA

by Pontifex
sim ⋮ 2,470 runs
Science Public Policy
859.0733
#198

Draining structure

by isee systems
Draining generic structire
model ⋮ 1,248 downloads
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draining generic structure decay
851.628
#199

Aquatic Trophic Productivity Model

by Ryan Bellmore
The ATP model is a dynamic food web simulation model.
sim ⋮ 2,287 runs
food webs river restoration fish biomass
822.87335
#200

Evolving Bits N=40

by Jon Darkow
sim ⋮ 2,473 runs
evolution bits receptor substrate
820.76
X

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 isee 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™.