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

Welcome to the isee Exchange™!


The Exchange is a repository of content created by Stella® users around the world. Scroll down to see featured items, search for specific items in the field above, or check out some common topics:



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If you own our Stella® Architect software, you can download assemblies—self-contained models that can be used as parts of other models—right here on the Exchange. Go here to view our assembly directory, and here to learn how assemblies can speed up and improve your modeling process.

We found 13 items
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#1

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 ⋮ 12,454 runs
asynchrony timing phenology climate change butterfly
19437.74
#2

Systems in Focus: Agriculture

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 ⋮ 6,224 downloads
Download Model
Systems in Focus agriculture cows dairy
6999.656
#3

Salmon Life Cycle Simulator

by Ryan Bellmore
sim ⋮ 1,713 runs
Pacific salmon life cycle modeling water temperature stream flow
1662.3267
#4

The Nassau Grouper (Epinephelus striatus)

by Sanelisa
Each life stage in the grouper life cycle represents the introduction of a possible policy to manage ... Read more
Each life stage in the grouper life cycle represents the introduction of a possible policy to manage the addressed specie. Effective strategies to enhance this fishery resource hinges on focusing on a particular life stage in the grouper life cycle then introducing a method to promote the population dynamics in these aggregation sites to protect future stocks.
model ⋮ 142 downloads
Download Model
Environment Aggregation Sites-Transient Spawning-Marine Reserves-Lunar Phase-Population Dynamics-The Bahamas
334.08267
#5

Sustainable Zero Waste Tyre Life Cycle

by Aldrich
About 5 million tyres are disposed of every year in New Zealand and 70 per cent end up in a landfill ... Read more
About 5 million tyres are disposed of every year in New Zealand and 70 per cent end up in a landfill. These tyres occupy a considerable amount of space. Often unaccounted for after disposal, tyre dumps eventually attract rats and other contaminants which may disrupt nearby environmental ecosystems in a way such as soil pollution. The standard is such that there is a difficulty with regards to recycling tyres due to the lack of an efficient system, tools, mechanics or even a commercial product that makes use of used tyres. As a result, tyres are quickly forgotten after disposed. This is an important problem in New Zealand with disastrous longer term environmental effects if not dealt with in the next few years.
sim ⋮ 122 runs
sustainable zero waste tyres life cycle recycling
141.882
#6

Crypto life cycle

by Christopher Huston
This is a compartment-based model to simulate Cryptosporidium population dynamics within a host
model ⋮ 73 downloads
Download Model
Biology
28.73
#7

sponges.cycle

by CAROLINA DOYA LE BESNERAIS
this model is only a portion of the model that I want to create. The later model objective is to dil ... Read more
this model is only a portion of the model that I want to create. The later model objective is to diludate how is the life cycle of those animals
model ⋮ 41 downloads
Download Model
trial
17.91
#8

Life Cycle of Co in LIB

by Lihua Wang
model ⋮ 23 downloads
Download Model
Science Education
12.13
#9

PLC

by Fernando Palomera
Product Life Cycle
model ⋮ 25 downloads
Download Model
7.4
#10

ATPU/RAZO life cycle graphs

by Sdurham2
model ⋮ 27 downloads
Download Model
7.02
#11

Test

by Jamie You
life cycle benefit
model ⋮ 18 downloads
Download Model
5.58
#12

Lab 3 - Life Cycle Assessment

by Kimberly Mendoza
model ⋮ 2 downloads
Download Model
0.52
#13

Salmon Life Cycle Simulator (Fish Creek, Juneau, AK)

by Ryan Bellmore
sim ⋮ 54 runs
-1.16
X

Uploading a Bundle from Zip

Instead of creating bundles, categories, and assemblies one by one, you can upload a single zip file that contains all of your bundle's content. To create your zipped bundle, make a folder with your bundle's name and add subfolders with your categories' names. The folder tree should have the same structure that you want the categories to have in your bundle. Place your assembly .stmx files in the appropriate category folders, then zip your bundle folder and upload it using the Upload Bundle from Zip link above.

Assemblies, Bundles, and Categories

Assemblies are self contained models that demonstrate common ways to connect together building blocks and that can be used as parts of other models. This is analogous to using prefabricated wall and roof pieces to construct a house.

Bundles are groups of assemblies with a common use or theme. For example, a Health Care bundle might contain a variety of assemblies that aid in creating health care models. When you download assemblies from the isee Exchange™, you download an entire bundle, rather than individual assemblies.

Categories are subgroups of assemblies within a bundle. For example, a Health Care bundle might contain a Funding category for assemblies related to the management of hospital funds. All assemblies must be assigned to a category—they cannot be assigned to the root of a bundle.

Assemblies, bundles, and categories can be created and uploaded to the isee Exchange™ via the options on the Manage My Assemblies page. To learn more, visit our help pages, or take our assemblies tutorial.

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™.