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.

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.

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".

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.

© 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.

© Jefferson Rajah & Martin Grimeland 2022 Considering the complex and dynamic nature of food systems, the System Dynamics method was opted for investigating the questions posed. Representing the real-world system responsible for farmers´ livelihoods, a simulation SD model was constructed as a proof-of-concept for the councils' policy strategy. It is evident, based on the findings of the model, that increasing food system literacy does indeed increase the resilience of SME farmers' livelihoods.

Will Noyes, Faith Kiprono & Min Xiang 2020 This project aims to help Bergen meet the T9 goal that ‘all new passenger cars are fossil-free from 2025’. The project intends to identify the underlying causal relationships linking the different factors affecting a 100 % switch to fossil-free passenger vehicles.

Prey and predators appear to follow population trends based on one another; this trend is known as the predator-prey cycle. Through the model the cycle will be analyzed in relation to snowshoe hare and Canada lynx populations from the mid-1800s to the mid-1900s in North America.

Species richness on island measured considering extra external factors. Based on island biogeographic theory and species richness curve.