Knowledge Representation Systems
May 26, 2006: PowerLoom® version 3.2 is released. PowerLoom license is now open source.
May 7, 2004: Loom® license is now open source.
January 23, 2003: Ontology Resources have been added to our site.
March 28, 2002: Ontosaurus 1.9 has been released!
July 12, 1999: Loom® 4.0 is available.
Loom and PowerLoom software is licensed
under open source licenses, but it remains the intellectual property of
the University of Southern California and it is not in the public
domain.
Knowledge Representation Systems| PowerLoom® | Loom® | |
|---|---|---|
Overview: Loom Knowledge Representation SystemA Quicktime movie describes how the classifier aids the development and automatically maintains the organization of a knowledge base.
The Loom system implements a logic-based pattern matcher that drives a production rule facility and a pattern-directed method dispatching facility that supports the definition of object-oriented methods. The high degree of integration between Loom's declarative and procedural components permits programmers to utilize logic programming, production rule, and object-oriented programming paradigms in a single application. Loom can also be used as a deductive layer that overlays an ordinary CLOS network. In this mode, users can obtain many of the benefits of using Loom without impacting the function or performance of their CLOS-based applications. A Retrospective on Loom provides more details.
Loom has been distributed to more than 80 universities and corporations, and is being used in numerous DARPA-sponsored projects in planning, software engineering and intelligent integration of information.
Loom ProjectsLoom is being used in the JFACC project. This is a DARPA project to develop a tool to assist the Joint Forces Air Component Commander create air campaign plans. One application developed with Loom for this project is the Strategy Development Assistant (SDA). A description of the project is contained in our Final Report for the project.
Ontosaurus, a Web-based browser for Loom and PowerLoom knowledge bases is under development. This provides a dynamnically generated, hyper-linked interface to Loom and PowerLoom theories.
Loom was applied to the domain of computer image understanding in the VEIL project, an experiment that links a Loom-based domain model with geometric objects produced by an image understanding program. The use of a Loom superstructure enables interaction with the image system at a higher-level of abstraction--discourse is at the level of domain concepts such as buildings, headquarters and events rather than pixels or cubes.
The EXPECT project uses Loom as the representation language for constructing knowledge acquisition tools. EXPECT is developing a knowledge acquisition framework that empowers users and domain experts to augment, modify and adapt knowledge based systems without needing to understand the details of the system's implementation.
SIMS provides intelligent access to heterogeneous, distributed information sources (databases, knowledge bases, flat files, programs, etc.), while insulating human users and application programs from the need to be aware of the location of the sources, their query languages, organization, size, etc. A fixed vocabulary describing objects in the domain, their attributes and relationships among them is created using Loom. SIMS then accepts queries in this high-level uniform language.
To implement PowerLoom we developed a new programming language called STELLA, which is a Strongly Typed, Lisp-like LAnguage that can be translated into Lisp and C++. STELLA tries to preserve those features of Lisp that facilitate symbolic programming and rapid prototyping, while still allowing translation into readable as well as efficient C++ code.
Loom and PowerLoom are registered trademarks of the University of Southern California.
