User Manual
This is the electronic version of the user manual of the Cassandra platform. The source code of the early prototype of the platform is located at: https://github.com/cassandra-project/platform. A working version of the platform can be found at: https://cassandra.iti.gr:8443/cassandra/app.html.
The platform is user oriented in the sense that each user has her own workspace consisting of her own projects and a private user library for storing entities for reuse. Before entering the platform the user should be authorized by the system using the necessary credentials (username and password).
Potential users should contact the system administrator in order to acquire appropriate credentials, since there is no self-registration procedure.
The Cassandra platform user interface is separated into three panes:
- The projects' or workspace pane, at the left of the screen (My Projects),
- the working pane at the middle of the screen (Main Panel) and the
- libraries pane on the right part of the screen (Libraries).
The libraries pane includes both the User library tree and the Cassandra library tree.
The workspace pane holds the projects of the user in a tree structure as follows:
- Projects (Level 0)
- Project (Level 1)
- Scenarios (Level 2)
- Scenario (Level 3)
- Installations (Level 4)
- Installation (Level 5)
- Persons (Level 6)
- Person (Level 7)
- Activities (Level 8)
- Activity (Level 9)
- Activity Models (Level 10)
- Activity Model (Level 11)
- Appliances (Level 6)
- Appliance and Consumption Model (Level 7)
- Simulation Parameters (Grid) (Level 4)
- Simulation Parameters (Form) (Level 5)
- Demographics (Grid) (Level 4)
- Demographics (Form) (Level 5)
- Pricing Schemes (Level 2)
- Pricing Scheme (Level 3)
- Runs (Level 2)
- Run (Level 3)
- CSNs (Level 2)
- CSN (Level 3)
Each tree node, represents an entity. Click on the links to see instructions about individuals entities. Each node opens in a tab on the working pane upon double-clicking on it.
The libraries (User and Cassandra) contain pre-specified entities that can be drag'n'dropped into working scenarios to facilitate scenario building. The supported entities are of type:
- Installation (along with its Person and Appliance entities and their children entities),
- Person (along with its children entities)
- Appliance (along with its Consumption Model)
- Activity Model (along with their Distributions)
- Pricing Schemes
The User library is a read-write library, i.e. a library that the user can store and retrieve entities, while the Cassandra library is read-only, meaning that the user can only get entities and not put.
Once a model is placed from a library into a scenario or vice-versa, a copy of the entity is created under the scenario, which can be further customised according to user needs. The user can also store models produced in any scenario from the workspace into the user library for future use. The cassandra library is updated by system administrators only. In general copies are recursive (deep copies), that is they copy recursively all the entities under the entity being drag'n'dropped. If you want a shallow copy then the Shift key must be kept pressed while dragging and dropping an entity. In the special case of an Activity Model, if the appliances are not copied as well (i.e. via a deep copy of an installation) the appliances participating in the activity model are dropped.
The main usage workflow is as follows:
- The user creates a scenario under a project and setups all the necessary entities and along with their properties: Installations, Persons, Appliances, Activities, Activity Models etc.
- The user specifies the simulation parameters.
- The user runs the scenario.
- The user double-clicks on the run after it finishes in order to see the results of the simulation. The results open in a new tab on the browser window.
- The user can run alternative scenarios by changing for example Appliances, Activity Models, Pricing Schemes etc.
- The user can also compare two runs by selecting two runs (pressing Ctrl while selecting) in the Runs grid tab and then by selecting the compare option from the menu.
- In the end the user can download the csv file for post-analysis through external tools like R and Matlab.
It is possible to automatically compute model parameters based on measurements obtained from actual consumer installations. This will allow analysis of consumption, as well as the accurate simulation of a range of ‘what if’ type scenarios. The Training and Response module (source, manual) will be responsible for this process.