Model scope and methods - WITNESS: Difference between revisions

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WITNESS stands for "World environmental ImpacT aNd Economics ScenarioS".
WITNESS stands for "World environmental ImpacT aNd Economics ScenarioS".


It is a global Integrated Assessment Model (IAM) framework, covering the world globally (regionalization and sectorization are in progress to be fully completed by end'24). The framework covers MacroEconomics, Energy, Materials, Natural resources, Environment, Population and Public Policies - mostly endogenous and fully coupled (i.e. taking into account all the feedback loops representing mutual interactions between models).
It is a global Integrated Assessment Model (IAM) framework, covering the world globally (regionalization and sectorization are in progress to be fully completed by end'24). The framework covers MacroEconomics, Energy, Materials, Natural resources, Environment, Population and Public Policies - mostly endogenous and fully coupled (i.e. taking into account all the feedback loops representing mutual interactions between models).[[File:WITNESS Overview.png|alt=WITNESS high level system view|none|thumb|895x895px|WITNESS high level system view]]
Most of the models are based on equations rather than data analysis and extrapolation, and the feedback loops generated by models interdependencies are efficiently and largely automatically tackled by the underlying simulation platform specifically developed to support it. 


The methodological approach to implementing WITNESS is to apply complex [http://en.wikipedia.org/wiki/System of systems/ system of systems] simulation techniques to IAM modelling ([http:///hal.science/hal-04227335/document more details on system of systems simulation]), with the high level system view presented below:
This simulation platform called SoSTrades (which stands for "System of Systems Trades"), and can by the way be used independently as a generic and powerful Multi-Disciplinary Analysis and Optimization ( [http:///en.wikipedia.org/wiki/Multidisciplinary design optimization MDAO] ) simulation platform.
[[File:WITNESS Overview.png|alt=WITNESS high level system view|none|thumb|500x500px|WITNESS high level system view]]
 
Most of the models are based on equations rather than data analysis and extrapolation, and the feedback loops generated by models interdependencies are efficiently and largely automatically tackled by the underlying simulation platform specifically developed to support it.  
 
The primary goal of WITNESS is to enable collaborative exploration of potential transition paths through simulation, pinpointing the key drivers that could steer these changes and the importance of feedback loops effects. Such a joint exploration aims to foster consensus on target trajectory envelopes, which is crucial for rallying a critical mass of stakeholders. Such collective agreement and engagement are seen as instrumental in successfully transitioning complete ecosystems.
 
 
Additionally, there’s an emphasis on risk estimation. This involves measuring the deviation between the planned trajectory and the worst possible scenarios, providing a quantitative assessment of risks associated with the transition. This metric serves as a vital tool for decision-makers to evaluate and manage potential uncertainties and challenges that may arise during the transition period.


This simulation platform called SoSTrades (which stands for "System of Systems Trades"), and can by the way be used independently as a generic and powerful [http:///en.wikipedia.org/wiki/Multidisciplinary design optimization MDAO] simulation platform and is an extension of the specialized [http:///gemseo.readthedocs.io/en/stable/index.html GEMSEO] library.  
This simulation platform called SoSTrades (which stands for "System of Systems Trades"), and can by the way be used independently as a generic and powerful [http:///en.wikipedia.org/wiki/Multidisciplinary design optimization MDAO] simulation platform and is an extension of the specialized [http:///gemseo.readthedocs.io/en/stable/index.html GEMSEO] library.  


= WITNESS framework =
= WITNESS framework =
At the top level, the system of systems approach define high level systems and their interactions (which you can roughly see in the picture above). From an implementation point of view, they will define [http:///en.wikipedia.org/wiki/Namespace namespaces] within which sub-system models will interact and exchange. An [http:///en.wikipedia.org/wiki/Ontology (information science) ontology] is also defined to formalize all modules and parameter's names. In the main namespace, all interfaces exposed by each of the main systems are automatically coupled using the ontology [http:///en.wikipedia.org/wiki/Semantic Web semantic] and [http:///en.wikipedia.org/wiki/Multidisciplinary design optimization multidisciplinary analysis and optimization (MDAO)] computational methods.
WITNESS applies complex [[wikipedia:System of systems|system of systems]] (1) simulation techniques to IAM modelling , applying a [[wikipedia:Systems engineering|system engineering]] approach starting from the high level system view presented in the picture above with their interactions.  
 
Going down recursively refining each system is similar, you will define sub-namespaces for each sub-system you identify to further refine it if needed, and you will define your current systems interfaces to let them be automatically be coupled through the ontology in your current namespace.


This methodology allow for easy refinement of models as the models interconnexions are prescriptive (expose interfaces in specific namespaces) but not descriptive (connections handling is automated an holistic within namespace). You can also decide to replace in some area the driver running multidisciplinary analysis (MDA), by a controller running multi-disciplinary optimization (MDO) of you want to orient the result vs an objective or want to respect specific constraints.  
This methodology allows easy and modular refinement of various systems, as well as rigorous handling of all the interactions and feedback loops between them. It also allows to leverage a full range of numerical multi-disciplinary analysis and optimization ([[wikipedia:Multidisciplinary design optimization|MDAO]]) methods and tools to build a complete world transition model.


For example in the basic WITNESS framework, an MDO controller is optimizing ventilation of available investment from Macro-economy to various Energy production techniques in Energy system, in order to maximize energy production while minimizing emissions under resources and materials contraints (more details [http:///www.witness4climate.org/optimizing-investments-in-energy-production-technology/ here]).
For example in the basic WITNESS framework, an MDO controller is optimizing ventilation of available investment from Macro-economy to various Energy production techniques in Energy system, in order to maximize energy production while minimizing emissions under resources and materials contraints (more detailes [https://www.witness4climate.org/optimizing-investments-in-energy-production-technology/ here]).


= SoSTrades simulation platform =
= SoSTrades simulation platform =
The SoSTrades simulation platform is a cooperative platform with a multi-user web front-end and cloud backend (Docker/Kubernetes).
SoSTrades is a multi-purpose and generic simulation management and execution platform, designed to explore complex system of systems scenarios in a collaborative way. It provides a a multi-user web front-end and cloud scalable backend to run and couple [[wikipedia:Containerization (computing)|containerized models]].
 
The model themselves are written in Python language and wrapped in an SoSTrades discipline that integrate model code, documentation, interfaces... Models not written in Python or requesting specific setup (libraries, licenses, computing infrastructure...) can be integrated through a REST API (or any available python mechanism).
 
Coupling of the models is performed using an extended / improved version of [http:///gemseo.readthedocs.io/en/stable/index.html GEMSEO] library, that is providing various applied mathematics standard solvers implementation. The platform facilitated usage of full [http:///en.wikipedia.org/wiki/Adjoint state method adjoint] based optimization by consistently managing gradients, that makes optimization cost almost independent of the number of parameters used. Those gradient also enable sensitivity analyses.


The platform itself can be used through a REST API to setup / run / analyse a scenario, and generate a synthesis HTML widget that can be embedded in some external dashboard.
The model themselves are written in (or accessed through) Python language and handling their interactions is largely automated, facilitating evolutions or additions of new models.


= Development team =
= Development team =
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Their development is strongly supported by [http:///www.capgemini.com/ Capgemini], which is also providing industrial grade deployment and support option, as well as several extensions to derive from WITNESS generated transition scenario various enterprise strategy models.
Their development is strongly supported by [http:///www.capgemini.com/ Capgemini], which is also providing industrial grade deployment and support option, as well as several extensions to derive from WITNESS generated transition scenario various enterprise strategy models.


More details can be found on [http:///www.witness4climate.org/world-environmental-impact-and-economics-scenarios/ witness4climate.org] website.{{ModelDocumentationTemplate
More details can be found on [http:///www.witness4climate.org/world-environmental-impact-and-economics-scenarios/ witness4climate.org] website.
 
(1) Charaf Eddine Dridi, Belala Faiza. [https://hal.science/hal-04227335/document System of Systems Modelling: Recent work Review and a Path Forward].  - ICAASE’20, Oct 2020, Constantine, DZ, France. ffhal-04227335f{{ModelDocumentationTemplate
|IsDocumentationOf=WITNESS
|IsDocumentationOf=WITNESS
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Revision as of 10:56, 22 August 2024

Model scope

WITNESS stands for "World environmental ImpacT aNd Economics ScenarioS".

It is a global Integrated Assessment Model (IAM) framework, covering the world globally (regionalization and sectorization are in progress to be fully completed by end'24). The framework covers MacroEconomics, Energy, Materials, Natural resources, Environment, Population and Public Policies - mostly endogenous and fully coupled (i.e. taking into account all the feedback loops representing mutual interactions between models).

WITNESS high level system view
WITNESS high level system view

Most of the models are based on equations rather than data analysis and extrapolation, and the feedback loops generated by models interdependencies are efficiently and largely automatically tackled by the underlying simulation platform specifically developed to support it.

This simulation platform called SoSTrades (which stands for "System of Systems Trades"), and can by the way be used independently as a generic and powerful Multi-Disciplinary Analysis and Optimization ( MDAO ) simulation platform.


The primary goal of WITNESS is to enable collaborative exploration of potential transition paths through simulation, pinpointing the key drivers that could steer these changes and the importance of feedback loops effects. Such a joint exploration aims to foster consensus on target trajectory envelopes, which is crucial for rallying a critical mass of stakeholders. Such collective agreement and engagement are seen as instrumental in successfully transitioning complete ecosystems.


Additionally, there’s an emphasis on risk estimation. This involves measuring the deviation between the planned trajectory and the worst possible scenarios, providing a quantitative assessment of risks associated with the transition. This metric serves as a vital tool for decision-makers to evaluate and manage potential uncertainties and challenges that may arise during the transition period.

This simulation platform called SoSTrades (which stands for "System of Systems Trades"), and can by the way be used independently as a generic and powerful MDAO simulation platform and is an extension of the specialized GEMSEO library.

WITNESS framework

WITNESS applies complex system of systems (1) simulation techniques to IAM modelling , applying a system engineering approach starting from the high level system view presented in the picture above with their interactions.

This methodology allows easy and modular refinement of various systems, as well as rigorous handling of all the interactions and feedback loops between them. It also allows to leverage a full range of numerical multi-disciplinary analysis and optimization (MDAO) methods and tools to build a complete world transition model.

For example in the basic WITNESS framework, an MDO controller is optimizing ventilation of available investment from Macro-economy to various Energy production techniques in Energy system, in order to maximize energy production while minimizing emissions under resources and materials contraints (more detailes here).

SoSTrades simulation platform

SoSTrades is a multi-purpose and generic simulation management and execution platform, designed to explore complex system of systems scenarios in a collaborative way. It provides a a multi-user web front-end and cloud scalable backend to run and couple containerized models.

The model themselves are written in (or accessed through) Python language and handling their interactions is largely automated, facilitating evolutions or additions of new models.

Development team

WITNESS and SoSTrades are part of Transition analysis project of the Open Source for Climate, part of the FINOS initiative from the Linux Foundation.

Their development is strongly supported by Capgemini, which is also providing industrial grade deployment and support option, as well as several extensions to derive from WITNESS generated transition scenario various enterprise strategy models.

More details can be found on witness4climate.org website.

(1) Charaf Eddine Dridi, Belala Faiza. System of Systems Modelling: Recent work Review and a Path Forward. - ICAASE’20, Oct 2020, Constantine, DZ, France. ffhal-04227335f

Alert-warning.png Note: The documentation of WITNESS is 'in preparation' and is not yet 'published'!

Model Documentation - WITNESS

Corresponding documentation
Previous versions
No previous version available
Model information
Model link
Institution Open-Source for Climate (OS-C), N/A, https://os-climate.org/transition-analysis/., Linux Foundation (LF), N/A, https://www.linuxfoundation.org/.
Solution concept Systems dynamics based approach
Solution method OptimizationSimulation-based optimization
Anticipation
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