The objective of the unified database (UDB) program was to develop an automated information system that would be useful in the design, development, testing, and support of new Air Force aircraft weapon systems. Primary emphasis was on the development of: (1) a historical logistics data repository system to provide convenient and timely access to…

This paper argues that an important design principle for building expert systems is to represent all control knowledge abstractly and separately from the domain knowledge upon which it operates. Abstract control knowledge is defined as the specifications of when and how a program is to carry out its operations, such as pursuing a goal, focusing,…

This paper examines the problem of automatic explanation of reasoning, or the ability of a program to discuss what it is doing in some understandable way, particularly as part of an expert system. An introduction presents a general framework in which to view explanation and reviews some of the research in this area. This is followed by a…

Presents results of five experiments on human information-seeking behavior in different online information-seeking environments which studied search strategies and assessed information value in realistic search environments. A conceptual model of how humans value information is presented. Empirical and modeling results are considered for…

This paper examines the search and selection strategies of teachers when retrieving information on computer assisted learning programs from an online database. A literature review covers cognitive factors in human computer interactions, database query and manipulation, cognitive style, and information searching. Several experiments are reported…