Sa'd+Shannak's Profile
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Date joined: Feb 23 2025
Sa'd+Shannak's Work
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wwef
Key Components of the System
Water:
Desalinated water (primary source in Qatar).
Groundwater
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Key Components of the System
Water:
Desalinated water (primary source in Qatar).
Groundwater and treated wastewater.
Water demand for agriculture, industry, and domestic use.
Energy:
Energy production (primarily from fossil fuels in Qatar).
Energy used for water desalination, food production, and waste management.
Food:
Food production (limited due to arid climate, heavily reliant on imports).
Food consumption and waste generation.
Waste:
Organic and inorganic waste from food, water, and energy sectors.
Waste treatment and recycling (e.g., composting, energy recovery).
Interdependencies and Feedback Loops
Water-Energy Nexus:
Desalination requires significant energy input.
Energy production (e.g., power plants) requires water for cooling.
Loop: Increased water demand → Increased energy demand → Increased water demand for energy production.
Energy-Food Nexus:
Energy is required for food production (irrigation, processing, transportation).
Food waste can be converted into energy (e.g., biogas).
Loop: Increased food demand → Increased energy demand → Increased food waste → Potential energy recovery.
Food-Water Nexus:
Agriculture requires water for irrigation.
Food waste contributes to water pollution if not managed properly.
Loop: Increased food production → Increased water demand → Increased food waste → Increased water pollution.
Waste-Energy-Water Nexus:
Waste treatment (e.g., wastewater treatment) requires energy.
Treated wastewater can be reused for irrigation or industrial purposes.
Loop: Increased waste generation → Increased energy demand for treatment → Increased water recovery → Reduced freshwater demand.
Stock-Flow Diagram Structure
Stocks:
Water reserves (desalinated, groundwater, treated wastewater).
Energy reserves (fossil fuels, renewable energy).
Food stocks (imported and locally produced).
Waste accumulation (organic, inorganic).
Flows:
Water flow: Desalination, groundwater extraction, wastewater treatment.
Energy flow: Energy production, energy consumption for desalination, food production, and waste management.
Food flow: Food production, consumption, and waste generation.
Waste flow: Waste generation, treatment, and recycling.
Feedback Loops:
Reinforcing loops: E.g., increased water demand leads to increased energy demand, which further increases water demand.
Balancing loops: E.g., waste-to-energy processes reduce waste accumulation and provide energy.
Example Loop: Water-Energy-Food-Waste
Water Demand Increases: Due to population growth or agricultural needs.
Energy Demand Increases: More energy is needed for desalination and water distribution.
Food Production Increases: More water and energy are used for agriculture.
Waste Generation Increases: Food waste and wastewater increase.
Waste Management Requires Energy: Energy is used to treat waste and recover resources.
Recycled Water and Energy: Treated wastewater is reused, and waste-to-energy processes provide additional energy.
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.
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.
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.
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™.