System Dynamics | Insight Maker

Evolution of Covid-19 in Brazil:

A System Dynamics Approach

Villela, Paulo (2020)
paulo.villela@engenharia.ufjf.br

This model is based on Crokidakis, Nuno. (2020). Data analysis and modeling of the evolution of COVID-19 in Brazil. For more details see full paper here.

Clone of Evolution of Covid-19 in Brazil: A System Dynamics Approach

Nilo Guimaraes

Clone of Clone of Investigation of Predator/Prey Modal 2

Laryza Lo-A-Foe

10 months ago

This model shows the changing happened in forest industry and mountain tourism in Derby Tasmania. Logging will degrade mountain tourism while benefit the forestry industry. Simulation borrowed from the Easter Island simulation.

According to the analysis, logging does not reduce tourism income. With the increase of number of bike guide, tourism income will increase as well. Also, in forest industry, timber income is higher than the harvest spending which means the industry always gain profits from logging. Therefore, the main concern is that the logging should be balanced between the Mountain Tourism and the forest industry.

Simulation of Derby Mountain bikes versus logging

Mirai

A new archetype, The Tyranny of Small Steps (TYST) has been observed. Explained through a system dynamics perspective, the archetypical behaviour TYST is an unwanted change to a system through a series of small activities that may be independent from one another. These activities are small enough not to be detected by the ‘surveillance’ within the system, but significant enough to encroach upon the “tolerance” zone of the system and compromise the integrity of the system. TYST is an unintentional process that is experienced within the system and made possible by the lack of transparency between an overarching level and a local level where the encroachment is taking place.

Reference:

Haraldsson, H. V., Sverdrup, H. U., Belyazid, S., Holmqvist, J. and Gramstad, R. C. J. (2008), The Tyranny of Small Steps: a reoccurring behaviour in management. Syst. Res., 25: 25–43. doi: 10.1002/sres.859

The Tyranny of small steps archetype (agent based)

H Haraldsson

3

A model that shows how the digital advertising market is growing and how Google's share in this market, and subsequently their financial results, are influenced by investing in either three of the policy variables.

Clone of Google Adwords Model

TBMOM Agency

This model (starting with a clone of a previous project on squirrels, mountain lions, and hunters) is a simplified version using only rabbits and snakes.

By modifying the birth and death rates, the variations in population change dramatically. Interestingly, in this iteration, the populations reach dismal lows, but always pick up later.

Rabbits and Snakes

Minh Nguyen

A model situmalte the relationship between moutain bikes and logging industry in Derby, Tasmania, It explains more when the number of visitors increases or decreses.

How the model works

The left side shows when the number of travellers increase, the income from travellers rental of bike and stay of hotel increase simultaneously. However, there is a capacity for both parking lots and hotel venues, which means that the top ability of hospitality of Derby. The right side shows the logging industry of Derby and income from logging. It has a impact on how travellers would value Derby moutain.

Insights

As the number of travellers increase, it increases the total income of Derby, and in return, the local government will re-revest in Derby Moutain and will also maintain the forrestry logging industry.

Simulation of Derby Moutain Bikes Versus Biking

Zhaofeng Liu

Instructions

Adjust values by using the sliders below or typing in values, then press "Simulate"

To find total cases or total cost with or without WGS, run the simulation twice with WGS = 0 and WGS = 1 (make sure you record the values each time)

Refresh page to restore default values

Warning:

Initial proportion of asymptomatically colonised patients + Initial proportion of symptomatically infected patients must be < 1

Proportion of admissions asymptomatically colonised + Proportion of admissions with symptomatic infection must be <1

Email amy.buchanan-hughes@costellomedical.com with queries or comments

Clone of C difficile and Whole Genome Sequencing

chlubna

hladina a tok

My Insight

Stanislava Mildeova

6 months ago

This model represents a repair contract to fix a group of houses with unresolved construction defects.

System Dynamics Model for repair cycle FUNCIONA

Nestor Ramirez

This forecasting model can be used to predict global data center electricity needs, based on understanding usage growth. Please note that the corresponding problem description, model developments, and results are discussed in the following paper:

Koot, M., & Wijnhoven, F. (2021). Usage impact on data center electricity needs: A system dynamic forecasting model. Applied Energy, 291, 116798. DOI: https://doi.org/10.1016/j.apenergy.2021.116798.

Usage impact on global data center electricity needs

M. Koot

6

Ciclo 1 extra repair consturction errors rework

Clone of Construction Rework SD

chikwa mwanza

Based on a dialogue on the System Dynamics mailing list regarding the current level of acceptance of System Dynamics after it has been promoted for over 40 years I dredged up the following set of influences as a thought exercise. This is an example of a Drifting Goals Systems Archetype.

Clone of Clone of Acceptance of System Dynamics

Erkki Laitila

Overview

A model which simulates the competition between logging versus adventure tourism (mountain bike ridding) in Derby Tasmania. Simulation borrowed from the Easter Island simulation.

How the model works.

Trees grow, we cut them down because of demand for Timber amd sell the logs.

With mountain bkie visits. This depends on past experience and recommendations. Past experience and recommendations depends on Scenery number of trees compared to visitor and Adventure number of trees and users. Park capacity limits the number of users.

Interesting insights

It seems that high logging does not deter mountain biking. By reducing park capacity, visitor experience and numbers are improved. A major problem is that any success with the mountain bike park leads to an explosion in visitor numbers. Also a high price of timber is needed to balance popularity of the park. It seems also that only a narrow corridor is needed for mountain biking

Clone of Simulation of Derby Mountain biking versus logging

James Ondari

Foxes initial population is doubled

Clone of Investigation of Predator/Prey Modal 1 Scenario 2

Rodrigo

This is a system dynamic model to describe relationship between local logging industry and biking tourism in Tasmanian Derby Mountain.

In the dynamic model, the left-hand side shows how Derby get income from local biking tourism. The biking visitors number are influenced by scenery evaluation which depend on local size of forest and influenced government policy support when Biking Tourism income is over 1000 unit. Biking visitors with good recommendation will also back to Mountain Derby and bring income for local in twice or more times. In the right-hand side, we found the income of logging industry was influenced by local logging growth rate and government policy if local Biking Tourism income is over 1000 unit. The increase of logging industry will also increase local employment which will influence employee cost. This factor will also affect total logging income in Derby Mountain.

The simulation results show, with governments support the Biking tourism will increase sharply in the first few years and finally instead local logging industry, at same time bring good environment and save local forest under local increase logging industry. The recommendation graph shows that, the number of good recommendation & bad recommendation for Derby Mountain biking tourism will also increase in high speed in front of few years with data fluctuation but finally maintain in a stable line. Last simulation graph shows that how policy factor influences logging and biking industry. The Government has strong support in local tourism, however, as number of tourists increase, the positive impact from government support will continue decrease. On the contrary, the government support influence will also decease to local logging industry when logging been instead by tourism.

Simulation Of Derby Mountain Bikes Versus logging

Zhuhang Wang

The main scope in this model is seeing how several variables can affect the amounCicl

Ciclo 3 construccion Funciona

Nestor Ramirez

Overview

A model which simulates the competition between logging versus adventure tourism (mountain bike ridding) in Derby Tasmania. Simulation borrowed from the Easter Island simulation.

How the model works.

Trees grow, we cut them down because of demand for Timber amd sell the logs.

With mountain bkie visits. This depends on past experience and recommendations. Past experience and recommendations depends on Scenery number of trees compared to visitor and Adventure number of trees and users. Park capacity limits the number of users.

Interesting insights

It seems that high logging does not deter mountain biking. By reducing park capacity, visitor experience and numbers are improved. A major problem is that any success with the mountain bike park leads to an explosion in visitor numbers. Also a high price of timber is needed to balance popularity of the park. It seems also that only a narrow corridor is needed for mountain biking

Clone of Simulation of Derby Mountain biking versus logging

Silong Lou

Problém časové alokace

Semestrální práce

V této simulaci můžeme pozorovat přibližnou dobu na dokončení projektu, který má zadané parametry, jenž ovlivňují dobu jeho dokončení. Zároveň také znázorňuje zjednodušené nabývání znalostí a nárůst (případně pokles) mzdy v poměru se znalostmi.

Celý model obsahuje 3 hladiny - vývojový čas, plat a znalosti vývojářů. Mezi parametry, jenž lze zadávat a jenž ovlivňují celkovou dobu vývoje, patří: počet vývojářů (1 - 10), základní mzda (35.000 - 120.000), termín (1 - 6) a obsáhlost projektu (0.4 - 2).

Celkový počet vývojářů a znalosti vývojářů ovlivňují výslednou mzdu jednotlivých vývojářů. Termín určuje za jak dlouhou dobu si přeje klient projekt dokončen (pravý čas se dozví v simulaci) a obsáhlost projektu představuje o jak velký projekt se jedná.

V simulaci lze pozorovat tři grafy. První porovnává požadovaný čas s reálným časem stráveným na projektu, spolu s křivkou komplexnosti jednotlivých prvků, které se vyskytly během vývoje. Druhý graf nám ukazuje nárůst znalostí aktuálního týmu (tým se znalostí 1 dokonale rozumí dané problematice) a na třetím grafu lze vidět vývoj mzdy vývojářů během projektu (mzda je závislá na znalostech, tedy graf má stejný tvar).

Clone of Problém časové alokace

Stanislava Mildeova

Based on model discussed by John D. Sterman (p 508) in All models are wrong: reflections on becoming a systems scientist (2002). Task: (A) Sketch what you think the resultant graph will be (see directions for drawing in model). (B) Then Run Simulation. Optional Extension: Replace Graph In/Out Flow connection with a connection from Trig. function. Repeat (A) & (B).

Sterman Model (2002)

wmstroup

15

Based on model discussed by John D. Sterman (p 508) in All models are wrong: reflections on becoming a systems scientist (2002). Task: (A) Sketch what you think the resultant graph will be (see directions for drawing in model). (B) Then Run Simulation. Optional Extension: Replace Graph In/Out Flow connection with a connection from Trig. function. Repeat (A) & (B).

Clone of Sterman Model (2002)

Kevin A. Nguyen

OBLIQUE THROW IN VACUUM

A body is thrown obliquely into the vacuum at an initial velocity of 100 m / s, in a direction that forms with the horizontal an angle x, such that sin (x) = 0.8 and cos (x) = 0.6. Adopting g = 10m / s², determine:

(a) the horizontal and vertical velocity component modules at the moment of launch;

(b) the instant at which the body reaches the highest point of its trajectory;

c) the maximum height reached by the body;

d) The range of the throw.

Source: RAMALHO, NICOLAU AND TOLEDO; Fundamentos de Física, Volume 1, 8th edition, pp. 12 - 169, 2003.

This model may be cloned and modified without prior permission of the authors. Thanks for quoting the source.

Lancamento obliquo no vacuo

Paulo Villela

7

Saving account

Léa Russell

Overview:

This model shows the relationship between the tourist industry and forestry industry in Derby Tasmania. It simulates the situation where these two competing industries can co-exist.

Methodologies:

Tourists are attracted by the beautiful scenery, good air quality and biodiversity in Mountain bike trail in Derby. The tourism income increase when more visitors are attracted to use the mountain bike trail.

The forestry industry generates revenue by logging and selling timber. Increasing timber supplied will destroy the forests, which makes the park less attractive for tourists.

However, the income from forestry and tourism can be used to improve the facilities in the park to attract more visitors.

Findings:

When the amount of timber supplied is less than the regrowth rate of forests, the tourism industry and forestry industry can co-exist. If amount of timber supplied excesses the regrowth rate, tourism industry will be negative impacted.

Simulation of Derby Mountain logging versus biking

Shaoyue Liu

System Dynamics Models