structured models of scientific concepts for organizing, accessing, and using learning materials
Concepts and their interrelationships are the fundamental building blocks for representing the phenomena investigated in mathematics, science, and engineering (MSE). The knowledge represented in learning materials for the sciences is typically organized around term-based or "weakly-structured" models of concepts and their interrelationships. We introduce a "strongly-structured" model of scientific concepts that provides the foundation for a knowledge base (KB) of concept representations. It focuses on such attributes as the objective representations, operational semantics, use, and interrelationships of concepts, all of which play important roles in constructing representations of phenomena that further understanding of MSE domains of knowledge.We have developed a strongly-structured model of concepts for SME domains in terms of a frame-based KRS with slots and attribute-value fillers. The model, whose framework is shown in Figure 1, is implemented as an XML schema. This schema is used as the basis for creating domain-specific KBs containing XML records of concepts.The Alexandria Digital Library (ADL) Digital Earth Testbed system (http://www.alexandria.ucsb.edu) has been extended with: (1) a KB of scientific concepts, from the domain of physical geography, that are represented in terms of our XML schema for concept representation; (2) a collection of heterogeneous learning materials exemplifying the concepts and their properties in various contexts; and (3) services that provide a variety of views of the content of the KB and associated collection. (Please refer to the JCDL paper "The ADEPT Digital Library Architecture" by Janee and Frew.) This extension to ADL is being deployed in teaching an introductory course in physical geography in Fall, 2002.
models concepts learning materials knowledge bases digital libraries physical geography teaching education ontologies