Semantic Information Management


Principal Investigator

Graduate Students

Project Overview


Semantic Information Management is a framework for Real-Time Collaborative Systems.

Knowledge sharing and collaboration has always been critical to human activity. Human societies function through cooperation and teamwork.  People exchange ideas, information and knowledge to achieve consensus-based decisions. The ubiquity of network connectivity and recent advances in computing technology has raised this interaction to a new level by introducing computer-mediated information sharing and consensus-based decision making in all facets of everyday life. Continuous advancement in technologies push the limits of the amount of information that can be processed and the rate at which it can be processed.
Clearly the trend is moving towards providing quality time on networks at a reasonable price. These developments in technology in various areas together with the advances in network related technology provides an excellent basis for supporting collaboration in variety of application areas. Application scenarios that are now feasible include:

Medical Telediagnosis: Paramedics rushing a patient from a distant location in an ambulance and collaborating with doctors at the hospital on the patient's E.K.G. The two locations are physically  separated and the paramedics will have low end processing while the doctors at the hospital will have relatively high end processing ability.
Crisis Management: Natural disaster relief and civil emergency teams manage and deploy assets and contribute critical information (from the site of the disaster) via symbols on terrain maps.
Mobile Office: A person in transit connects with the office to participate in a videoconference and accomplishes knowledge work.
Electronic Trading: A broker can now virtually trade on the trading floor from remote locations during travel. Number of brokers can collaborate to discuss using real-time quote inputs and market inputs from brokers at more than one location.

Software Architecture

The SIM framework has a three layer Architecure


The User Interface is independent of the SEM architecture. The user interface is the metaphor of the collaboration space where all the users interact.
The main constituents of the SEM Architecture are

The Application Interface is responsible for locally orchestrating an application client’s session. It monitors all objects of interest to the client and encodes their state as entries in the Globally Coordinated Object-State Table (GCOST). The client’s interest in this object and its current state is locally recorded by the Application Interface as an entry in GCOST.

The primary function of GCOST is to ensure that all instances of objects in the collaboration session have consistent state. The table is implemented as a coordinated hierarchical hash table.; Each client in the collaboration session maintains a local GCOST, and all local GCOST’s in a collaboration session are globally coordinated so that if an entry is exists in more than one GCOST, all its instances are consistent.

The semantic Information Interpreter is responsible (a) for associatively  multicasting events; over the communication media, and; (b) for interpreting incoming messages, corresponding to remote events, for relevance and translating them into local events.

For a typical interaction scenario click here.

Latest Developments

Watch for developments and Code
Annual CAIP Review Meeting Presentation.

Recent Advancements in SIM From SEM to SIM

Thesis Defence Presentation (05/21/99)

Some Other work that uses SIM modules



Special Problem: Report

           Pravin Bhandarkar, "An Adaptive Framework for Collaboration in Heterogeneous Environments", Masters Degree Thesis
           May 1999 ( ps version , doc version)

Conference Papers

Some Links

Common Object Request Broker Architecture (CORBA)

Java Programming

Design Patterns


Back to Home Page

Last updated: Mon  April 04  09:28:28 EDT 1999
By Pravin Bhandarkar

Please send your comments toDr.Parashar or Pravin