|Michael Genesereth on The Herbrand Manifesto - Thinking Inside the Box|
The traditional semantics for First Order Logic (sometimes called Tarskian semantics) is based on the notion of interpretations of constants. Herbrand semantics is an alternative semantics based directly on truth assignments for ground sentences rather than interpretations of constants. Herbrand semantics is simpler and more intuitive than Tarskian semantics; and, consequently, it is easier to teach and learn. Moreover, it is more expressive. For example, while it is not possible to finitely axiomatize integer arithmetic with Tarskian semantics, this can be done easily with Herbrand Semantics. The downside is a loss of some common logical properties, such as compactness and completeness. However, there is no loss of inferential power. Anything that can be proved according to Tarskian semantics can also be proved according to Herbrand semantics. In this presentation, we define Herbrand semantics; we look at the implications for research on logic and rules systems and automated reasoning; and and we assess the potential for popularizing logic.
|Michael Genesereth is an associate professor in the Computer Science Department at Stanford University. He received his Sc.B. in Physics from M.I.T. and his Ph.D. in Applied Mathematics from Harvard University. Genesereth is most known for his work on Computational Logic and applications of that work in Enterprise Management, Electronic Commerce, and Computational Law. He is one of the founders of Teknowledge, CommerceNet, and Mergent Systems. Genesereth is the current director of the Logic Group at Stanford and research director of CodeX(the Stanford Center for Computers and Law)|
|Thom Fruehwirth on Constraint Handling Rules|
|Constraint Handling Rules (CHR) is a concurrent committed-choice constraint logic programming language. It consists of guarded rules that transform multi-sets of atomic formulas (constraints) until exhaustion. In CHR, one can describe algorithms in a compact declarative way. It can directly embed many rule-based formalisms and systems. The clean logical semantics of CHR ensures that several desirable properties hold for proper CHR programs for free (such as incrementality). It also facilitates non-trivial program analysis (such as confluence). In particular, operational equivalence of terminating programs is decidable. Last but not least, we present typical academic and commercial applications from the international CHR community. They range from stock broking to a world record attempt in robot sailing.
Thom Frühwirth is the designer of the programming language Constraint Handling Rules (CHR) and author of the book by the same name. He has co-authored two leading textbooks on constraint programming and reasoning that became standard references for the research area. He has published more than 170 research papers in declarative programming and logical reasoning.
|CHR Keynote Talk Slides|
|Avigdor Gal on When Processes Rule Event Streams
Big Data brings with it new and exciting challenges to complex event processing. Large volumes of simple events that stream in high velocity to our processing stations from a variety of sources call for rethinking traditional methods of processing complex events. In this talk we shall explore the interesting phenomenon of event streams that are produced by processes, e.g., bus data that is governed by bus routes or real time positioning system tracking patients in an outpatient clinic. The talk shall answer some of the related interesting questions: how do we discover the rules that govern event creation? how do we use such rules to optimize complex event processing? and suggest directions for future research. The talk will be accompanied by examples of urban transportation in Dublin (the INSIGHT European project) and patient visits to Dana-Farber Cancer Institute (DFCI), a large outpatient cancer center in the US.
|Avigdor Gal is a faculty member at the Technion -- Israel Institute of Technology. His research focuses on effective methods of integrating data from multiple and diverse sources, which affect the way businesses and consumers seek information over the Internet. Prof. Gal has published more than 100 papers in leading professional journals, conferences, and books. He serves in various editorial capacities for periodicals and has helped organize professional workshops and conferences (e.g., BPM and DEBS) nearly every year since 1998. Avigdor is a member of the DEBS steering committee.|