Research Interests



Studies in Formal Logics, Uncertainty, and the Foundations of Artificial Intelligence

I have a long-standing interest in the study of intelligence and the development of mathematical models of natural human cognitive processes.  This has led to a theory of “qualified syllogisms'”, which can be applied to some well-known problems in the field of nonmonotonic reasoning.  That work includes a new kind of logical formalism, dubbed “Dynamic Reasoning Systems”, which explicitly portrays reasoning as an activity that takes place in time.  Another work has built on these ideas to create a Layman's Probability Theory for reasoning with linguistic likelihood (involving terms such as “likely,” “very likely,” “somewhat likely,” “unlikely,” etc.).  More recently I have applied these same methodologies to develop a model for agent-oriented epistemic reasoning, i.e., deductions involving dispositions of knowledge and belief and employed my notion of dynamic reasoning to formulate a process of belief revision.  Most recently I have been aiming this theory toward applications to mission planning for autonomous underwater vehicles.

Digital Libraries, Knowledge Management, and Applications for the Internet

Beginning in 1996 I undertook a project to develop a next-generation knowledge management system.  This applies 2D and 3D graphics and Internet/Intranet technology to the development of indexes for large distributed digital libraries, and in part utilizes the theory of Dynamic Reasoning Systems cited above.  These indexes take the form of concept taxonomies (semantic networks, ontologies) having a much richer semantic structure than simple trees.  In addition, the indexes are created by their communities of users and thus comprise knowledge bases that grow and evolve over time.  An underlying semantics and some reasoning algorithms will be provided that will enable users to query the index as to the deeper relations between classification categories.  Advanced graphics techniques will be employed to facilitate browsing, to help users find their way through these more complex structures without becoming lost or confused. I have continued to develop the various components of this system through an ongoing series of master’s degree programming projects.

Network Security, Intrusion Detection Systems, Unmanned Aerial Vehicles

In recent years I have developed a new interest in Information Security.  During May 2001 through April 2006 I was part of an eleven-investigator research project to study problems of critical infrastructure protection for the US Army. This work was done in collaboration with Sara Stoecklin, also at FSU, to develop a case-based reasoning (CBR) system for network intrusion detection. We employed two research assistants. The primary results were (1) an adaptive case-based reasoning framework employing reflective software architecture, and (2) application of this framework to build a multi-sensor intrusion detection system.  The latter became the topic of one student’s doctoral dissertation.  More recently I have become co-PI on a project funded by the US Navy to develop secure communications for unmanned aerial vehicles. 

 Selected Publications

·         Schwartz, D.G., A theory of event possibility with application to vehicle waypoint navigation, 36th North American Fuzzy Information Processing Society Annual Conference; proceedings published as Fuzzy Logic in Intelligent System Design: Theory and Applications, Advances in Intelligent Systems and Computing 648, Springer, 2017, pp. 329-334.

·         Schwartz, D. G, On the possibility of an event, Proceedings of the 18th International Conference on Artificial Intelligence (ICAI'16), July 25-28, 2016, Las Vegas, USA (held as part of WorldComp'16), pp. 47-51.

·         Schwartz, D. G., Dynamic reasoning systems, ACM Transactions on Computational Logic, 16, 4 (2015) Article 32, 69 pages including appendix.

·         Schwartz, D. G., Qualified syllogisms with fuzzy predicates, International Journal of Intelligent Systems, 29, 10 (2014) 926-945.

·         Schwartz, D.G., Agent-oriented epistemic reasoning: subjective conditions of knowledge and belief, Artificial Intelligence, 148, 1-2 (2003) 177-195.

·         Schwartz, D.G., Layman's probability theory: a calculus for reasoning with linguistic likelihood, Information Sciences, 126, 1-4 (2000) 71-82.

·         Schwartz, D.G., Time, nonmonotonicity, qualified syllogisms, and the frame problem, Journal of Intelligent Systems, 8, 3-4 (1998) 315-355.

·         Schwartz, D.G., Dynamic reasoning with qualified syllogisms, Artificial Intelligence, 93, 1-2 (1997) 103--167.

·         Schwartz, D.G., Klir, G.J., Lewis, H., and Ezawa, Y., Applications of fuzzy sets and approximate reasoning, Proceedings of the IEEE, 82, 4 (1994) 482-498.

·         Schwartz, D.G. and Klir, G.J., Fuzzy logic flowers in Japan, IEEE Spectrum, 29, 7 (1992) 32--35.

·         Schwartz, D.G., Fuzzy inference in a formal theory of semantic equivalence, Fuzzy Sets and Systems, 31 (1989) 205-216.

·         Schwartz, D.G., A free-variable theory of primitive recursive arithmetic, Zeitschrift für Mathematische Logik und Grundlagen der Mathematik, 33 (1987) 147-157.

·         Schwartz, D.G., On the equivalence between logic-free and logic-bearing systems of primitive recursive arithmetic, Zeitschrift für Mathematische Logik und Grundlagen der Mathematik, 33 (1987) 245-253.

·         Schwartz, D.G., Semantic completeness of free-variable theories, Zeitschrift für Mathematische Logik und Grundlagen der Mathematik, 33 (1987) 441-452.

·         Schwartz, D.G., Isomorphisms of G. Spencer-Brown's Laws of Form and F. Varela's Calculus for Self-Reference, International Journal of General Systems, 6 (1981) 239-255.

Complete List of Publications