that adding different forms of global counting restrictions to a logic may increase the complexity of the inference problems dramatically. We provide exact complexity results and a practical, tableau based algorithm for the DL SHIQ, which forms the basis of the highly optimized DL system iFaCT. Finally, we

This thesis discusses the use of the real numbers in theorem proving. Typically, theorem provers only support a few `discrete' datatypes such as the natural numbers. However the availability of the real numbers opens up many interesting and important application areas, such as the verification of floating point hardware and hybrid systems. It also allows the formalization of many more branches of classical mathematics, which is particularly relevant for attempts to inject more rigour into computer algebra systems. Our work is conducted in a version of the HOL theorem prover. We describe the rigorous definitional construction of the real numbers, using a new version of Cantor's method, and the formalization of a significant portion of real analysis. We also describe an advanced derived decision procedure for the `Tarski subset' of real algebra as well as some more modest but practically useful tools for automating explicit calculations and routine linear arithmetic reasoning. Finally,...

selected for presentation at the workshop and for inclusion in these Workshop Notes. We wish to thank the authors, members of the Program Committee, and the Additional Reviewers

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At ATR Spoken Language Translation Research Laboratories, we are building a broad-coverage bilingual corpus to study corpus-based speech translation technologies for the real world. There are three important points to consider in designing and constructing a corpus for future speech translation research. The first is to have a variety of speech samples, with a wide range of pronunciations and speakers. The second is to have data for a variety of situations. The third is to have a variety of expressions. This paper reports our trials and discusses the methodology. First, we introduce a bilingual travel conversation (TC) corpus of spoken languages and a broad-coverage bilingual basic expression (BE) corpus. TC and BE are designed to be complementary. TC is a collection of transcriptions of bilingual spoken dialogues, while BE is a collection of Japanese sentences and their English translations. Whereas TC covers a small domain, BE covers a wide variety of domains. We compare the characteristics of vocabulary and expressions between these two corpora and suggest that we need a much greater variety of expressions. One promising approach might be to collect paraphrases representing various different expressions generated by many people for similar concepts. 1.

be used, for instance, to build in special equational theories into theorem provers. The aim of UNIF 2004, as that of the previous meetings, is to to bring together people interested in unification, present recent (even unfinished) work, and discuss new ideas and trends in unification and related fields

deduction derives from the fact that the field traditionally focussed on the art of automatically finding proofs. Initially, researchers were mainly motivated by the wish to build computer systems that could automatically solve hard, mathematical problems. When searching for a very hard proof, it is quite acceptable for a system to eat up all resources and to never to give up. After all that is what we, researchers are also doing all the time. However in the last years, one has become aware of the fact that for many applications, one needs to take more of an engineer’s approach. In particular, one needs to be aware of resources. In order to use resources efficiently, it is essential to be able to efficiently recognize non-theorems. As an example, consider a situation where an automated theorem proving system is used as assistant for automatically solving subtasks in a larger, interactive project. In this context, the requirements to the automated theorem prover are quite different than in mathematics. In case, the user is working on a faulty conjecture, he should find out as early as possible. In addition, in case it cannot find a proof, the prover should provide as much information as possible, so that the user can correct

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