The ECOSIM Demonstrator (main server)

The ECOSIM server (demonstrator) is implemented on a UNIX workstation with a Xlib (X Windows) graphical user interface. Its basic user interface , display and analysis functionality will be based on the ACA ToolKit, that also defines a major part of the Development framework.

Please note that the ToolKit is ESS proprietary software and is introduced into ECOSIM as Background. The limitations on use, distribution and exploitation defined in the Project CONTRACT apply.

Main server functionality:

ECOSIM is designed as a distributed set of (logical) servers that provide a broad range of data and analysis tools (information resources) to the users through an interactive, graphical user interface. This modular, distributed system is and coordinated by the main ECOSIM Server.

Conceptually, the main ECOSIM Server provides the

• user interface in both the conceptual and physical, graphical sense, and manages and coordinates the
• information resources (data and tools) of the entire system, that are accessible through this user interface.

More specifically, the ECOSIM Server provides the core functionality of:

• the main user interface, including
• hypertext help- and explain functions,
• GIS and visualization tools for monitoring data and model (scenario) results and their associated (local) data management,
• support for WWW access to selected systems functions and data holdings,
• and coordination of major functional components (models) through
• domain-specific objects (such as, for example, emission sources and model scenarios) and their associated methods (information resources, which in turn can include local or distributed data and models), and
• the multi-criteria DSS part of the system.

Linked to this central server are external information resources which primarily include

• external data bases (for monitoring data and model scenarios)
• external models and tools (including high-performance parallel computer based models).

An example of the user interface and the model/GIS integration is provided by the AirWare air quality assessment and modeling system.
Server functionality includes the

1. top level start-up screen, showing systems identification and release information, with the

2. main icon menu, which offers:

3. entry to the hypertext help- and explain system, which provides a limited functionality HTML browser, based on the CERN libraries used for the Mosaic browser. The browser is fully integrated into the ECOSIM server, and uses standard URL referencing of hypertext content files or cgi scripts.

4. the geographical information system (GIS) (please note that there are several other links and entry points to the GIS, in particular for/from the display of spatial model results or the database interface and (spatial) data analysis functions). The GIS is primarily a repository of all spatially referenced information, i.e., maps, together with interactive display and basic analysis functionality.

5. the basic objects data base that represents the main elements of the urban environmental systems and their attributes and functions, and its embedded rule-based expert system

6. any case specific functionality, including a heterarchical decomposition of the spatial domain, and the various models or other specific information processing tools.

The main server is implemented on a (SUN) UNIX machine, and provides an X Windows (Xlib) based graphical user interface. This can also support PC clients in a local network running an X Windows emulation (under DOS, MS Windows, Windows NT, or an Apple/McIntosh), for example, using Hummingbird's eXceed software.

Based on its client-server architecture the server communicates with the various distributed information resources either through its internal functions and local file system, or through the http (hypertext transfer) protocol to access distributed resources like data bases, monitoring systems, or simulation models.