Yannis Vassiliou

An optimizing prolog front-end to a relational query system

An optimizing translation mechanism for the dynamic interaction between a logic-based expert system written in PROLOG and a relational database accessible through SQL is presented. The mechanism makes use of an intermediate language that decomposes the optimization problem and makes the proposed approach target-language independent. It can either facilitate expert system - database interaction, e.g., when integrating expert systems into business systems, or augment existing databases with (external) deductive capabilities.

A Field Evaluation of Natural Language for Data Retrieval

Although a large number of natural language database interfaces have been developed, there have been few empirical studies of their practical usefulness. This paper presents the design and results of a field evaluation of a natural language system-NLS-used for data retrieval.

Access to Specific Declarative Knowledge by Expert Systems: The Impact of Logic Programming

As part of the operation of an Expert System, adeductive component accesses a database of facts to helpsimulate the behavior of a human expert in a particularproblem domain. The nature of this access is examined, andfour access strategies are identified. Features of each ofthese strategies are addressed within the framework of aLogic-based deductive component and the relational model ofdata.

Integrating Database Management and Expert Systems

Future Information Systems will include Large Scale Knowledge Bases and Reasoning components. The backbone of such systems will be provided by Artificial Intelligence and Databases. Specifically, by the technologies in the areas of Knowledge Based or Expert Systems and of Database Management Systems. As evidenced by several recent professional meetings and publications, the integration of the two technologies has attracted a large number of researchers.

Knowledge-based and database systems: enhancements, coupling or integration?

Position: The technologies in the areas of Knowledge Based or Expert Systems (KBS) and of Database Management Systems (DBMS) will play a major role in future Information Systems. Research issues present in a combined use of the two technologies have attracted researchers, both from Artificial Intelligence and Databases.

Coupling field studies with laboratory experiments for the evaluation of computer languages

Most evaluations of computer languages have used laboratory experiments as the basis of their research design [ll. While much has been learned from these studies, they all suffer from a number of defects including unrealistic subject populations, a narrow focus, a lack of strength of the independent variables and artificiality of the experimental situation. In order to overcome these limitations in research design, the Advanced Language Project (ALP) at NYU combined laboratory experiments with a field study, in a coordinated manner, to investigate the practicality of using natural language for data base access.

Requirements for Developing Natural Language Query Applications

The use of a “natural language” (for example, English) for direct interaction with databases, promises to broaden the market and the scope of computer utilization.(9,16,20,24) Technical feasibility has been demonstrated by the large number of experimental systems and the commercial availability of at least one such system. Yet there are many who voice concern as to the usability of natural languages for database querying by emphasizing the inherent dangers from its ambiguity.(17)