Modelling Users, Intentions, and Structure in Spoken Dialog

We outline how utterances in dialogs can be interpreted using a partial first order logic. We exploit the capability of this logic to talk about the truth status of formulae to define a notion of coherence between utterances and explain how this coherence relation can serve for the construction of AND/OR trees that represent the segmentation of the dialog. In a BDI model we formalize basic assumptions about dialog and cooperative behaviour of participants. These assumptions provide a basis for inferring speech acts from coherence relations between utterances and attitudes of dialog participants. Speech acts prove to be useful for determining dialog segments defined on the notion of completing expectations of dialog participants. Finally, we sketch how explicit segmentation signalled by cue phrases and performatives is covered by our dialog model.Comment: 17 page

Combining Expression and Content in Domains for Dialog Managers

We present work in progress on abstracting dialog managers from their domain in order to implement a dialog manager development tool which takes (among other data) a domain description as input and delivers a new dialog manager for the described domain as output. Thereby we will focus on two topics; firstly, the construction of domain descriptions with description logics and secondly, the interpretation of utterances in a given domain.Comment: 5 pages, uses conference.st

Metrics for Measuring Data Quality - Foundations for an Economic Oriented Management of Data Quality

The article develops metrics for an economic oriented management of data quality. Two data quality dimensions are focussed: consistency and timeliness. For deriving adequate metrics several requirements are stated (e. g. normalisation, cardinality, adaptivity, interpretability). Then the authors discuss existing approaches for measuring data quality and illustrate their weaknesses. Based upon these considerations, new metrics are developed for the data quality dimensions consistency and timeliness. These metrics are applied in practice and the results are illustrated in the case of a major German mobile services provider

Changing Views of Nature (Flyer)

Professor Heinrich has published over twenty books on natural history, including Bumblebee Economics and Winter World: The Ingenuity of Animal Survival, a New York Times bestseller. Among many other awards, he has received the Guggenheim Fellowship, the Alexander von Humboldt Senior Scientist Fellowship Award, the John Burroughs Medal for Nature Writing (for Mind of the Raven, a New York Times “Notable Book of the Year”), the Pen New England Book Award for non-fiction (for Life Everlasting), the Henry David Thoreau Prize for Literary Excellence in Nature Writing. He is also a noted ultra-marathon runner, as he writes about in his best-selling Why We Run and elsewhere; his running achievements have been recognized by the American Ultra-running Hall of Fame and other organizations

Iterative Differential Equations and Finite Groups

It is an old question to characterize those differential equations or differential modules, respectively, whose solution spaces consist of functions which are algebraic over the base field. The most famous conjecture in this context is due to A. Gorthendieck and relates the algebraicity property with the p-curvature which apprears as the first integrability obstruction in characteristic p. Here we prove a variant of Grothendieck's conjecture for differential modules with vanishing higher integrability obstructions modulo p - these are iterative differential modules - and give some applications

Differential Equations and Finite Groups

This note is devoted to linear differential equations with finite Galois groups. It is a famous conjecture due to A. Grothendieck that the finiteness of the differential Galois group should be equivalent to the triviality of the p-curvature for almost all p. The p-curvature is just the first integrability obstruction for the reduced differential equation in characteristic p. In the case all such integrability obstructions vanish in characteristic p we obtain a so-called iterative differential equation or iterative differential module, respectively. For these a nice Picard-Vessiot theory has been developed by M. van der Put and the author. In particular, the differential Galois groups are linear algebraic groups and there is a Galois correspondence. Thus a natural question arises, wether there exists a reasonable reduction theory preserving Galois groups etc. The corresponding objects in characteristic zero are iterative differential modules over iterative differential rings. The latter are suitable Dedekind subrings of algebraic function fields over number fields, here called global differential rings. These and the corresponding global differential modules are studied in Chapter 1. Chapter 2 presents the construction of global Picard-Vessiot rings (PV-rings) over global differential rings and proves that such PV-rings are generated by globally bounded power series as introduced by G. Christol. In Chapter 3 the reduction of global differential modules and their PV-rings is studied. The main result is that a global PV-ring in characteristic zero is algebraic if and only if for almost all primes p the reduced PV-ring is algebraic. Moreover, for almost all p the reduced PV-ring and the PV-ring of the modulo p reduced global differential module coincide. According to Grothendieck's p-curvature conjecture all global PV-rings are algebraic. Using the result above, this fact might be proven directly. This would already imply a nice algebraicity criterion for formal power series over number fields used by G. Eisenstein and could become a significant step towards the proof of Grothendieck's conjecture

Analysis of UV and EUV emission from impacts on the Sun after 2011 June 7 eruptive flare

On 2011 June 7 debris from a large filament eruption fell back to the Sun causing bright ultraviolet (UV) and extreme ultraviolet (EUV) splashes across the surface. These impacts may give clues on the process of stellar accretion. The aim is to investigate how the impact emission is influenced by structures in the falling ejecta and at the solar surface. We determine the UV and EUV light curves of a sample of impacts. The ballistic impact velocity is estimated from the ejection and landing times and, where possible, compared with the velocity derived by tracking the downflows in SDO/AIA and STEREO/EUVI images. Estimates of the column density before impact are made from the darkness of the falling plasma in the 193 A channel. The impact velocities were between 230 and 450 km/s. All impacts produced bright EUV emission at the impact site but bright UV was only observed when the impacting fragments reached the chromosphere. There was no clear relation between EUV intensity and kinetic energy. Low UV to EUV intensity ratios (I{UV}/I{EUV}) were seen (i) from impacts of low column-density fragments, (ii) when splashes, produced by some impacts, prevented subsequent fragments from reaching the chromosphere, and (iii) from an impact in an active region. The earliest impacts with the lowest velocity (~250 km/s) had the highest I{UV}/I{EUV}. The I{UV}/I{EUV} decreases with impact velocity, magnetic field at the impact site, and EUV ionising flux. Many of the infalling fragments dissipate above the chromosphere either due to ionisation and trapping in magnetic structures, or to them encountering a splash from an earlier impact. If the same happens in accreting stars then the reduced X-ray compared to optical emission that has been observed is more likely due to absorption by the trailing stream than locally at the impact site.Comment: 10 pages, 14 figures To be published in A&