@inproceedings{deKoterVinkMuijres2007,
  author    = {de Koter, A. and Vink, J. S. and Muijres, L.},
  title     = {Constraints on wind clumping from the empirical mass-loss vs. metallicity relation for early-type stars},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17736},
  year      = {2007},
  abstract  = {We present the latest results on the observational dependence of the mass-loss rate in stellar winds of O and early-B stars on the metal content of their atmospheres, and compare these with predictions. Absolute empirical rates for the mass loss of stars brighter than 10\$^{5.2} L_{\odot}\$, based on H\$\alpha\$ and ultraviolet (UV) wind lines, are found to be about a factor of two higher than predictions. If this difference is attributed to inhomogeneities in the wind this would imply that luminous O and early-B stars have clumping factors in their H\$\alpha\$ and UV line forming regime of about a factor of 3--5. The investigated stars cover a metallicity range \$Z\$ from 0.2 to 1 \$Z_{\odot}\$. We find a hint towards smaller clumping factors for lower \$Z\$. The derived clumping factors, however, presuppose that clumping does not impact the predictions of the mass-loss rate. We discuss this assumption and explain how we intend to investigate its validity in more detail.},
  language  = {en}
}
@inproceedings{ReyesIturbideVelazquezRosado2007,
  author    = {Reyes-Iturbide, J. and Vel{\´a}zquez, P. and Rosado, M.},
  title     = {3D numerical model for an asymmetrical superbubble},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17724},
  year      = {2007},
  abstract  = {Massive stars usually form groups such as OB associations. Their fast stellar winds sweep up collectively the surrounding insterstellar medium (ISM) to generate superbubbles. Observations suggest that superbubble evolution on the surrounding ISM can be very irregular. Numerical simulations considering these conditions could help to understand the evolution of these superbubbles and to clarify the dynamics of these objects as well as the difference between observed X-ray luminosities and the predicted ones by the standard model (Weaver et al. 1977).},
  language  = {en}
}
@inproceedings{GrohHillierDamineli2007,
  author    = {Groh, J. H. and Hillier, D. J. and Damineli, A.},
  title     = {Mass-loss rate and clumping in LBV stars : the impact of time-dependent effects},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17773},
  year      = {2007},
  abstract  = {This paper outlines a newly-developed method to include the effects of time variability in the radiative transfer code CMFGEN. It is shown that the flow timescale is often large compared to the variability timescale of LBVs. Thus, time-dependent effects significantly change the velocity law and density structure of the wind, affecting the derivation of the mass-loss rate, volume filling factor, wind terminal velocity, and luminosity. The results of this work are directly applicable to all active LBVs in the Galaxy and in the LMC, such as AG Car, HR Car, S Dor and R 127, and could result in a revision of stellar and wind parameters. The massloss rate evolution of AG Car during the last 20 years is presented, highlighting the need for time-dependent models to correctly interpret the evolution of LBVs.},
  language  = {en}
}
@inproceedings{OPUS4-1412,
  title     = {The 3rd international IEEE scientific conference on physics and control (PhysCon 2007) : September 3rd-7th 2007 at the University of Potsdam},
  editor    = {Kurths, J{\"u}rgen and Fradkov, Alexander and Chen, Guanrong},
  publisher = {Universit{\"a}tsverlag Potsdam},
  address   = {Potsdam},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-15228},
  pages     = {345},
  year      = {2007},
  abstract  = {During the last few years there was a tremendous growth of scientific activities in the fields related to both Physics and Control theory: nonlinear dynamics, micro- and nanotechnologies, self-organization and complexity, etc. New horizons were opened and new exciting applications emerged. Experts with different backgrounds starting to work together need more opportunities for information exchange to improve mutual understanding and cooperation. The Conference "Physics and Control 2007" is the third international conference focusing on the borderland between Physics and Control with emphasis on both theory and applications. With its 2007 address at Potsdam, Germany, the conference is located for the first time outside of Russia. The major goal of the Conference is to bring together researchers from different scientific communities and to gain some general and unified perspectives in the studies of controlled systems in physics, engineering, chemistry, biology and other natural sciences. We hope that the Conference helps experts in control theory to get acquainted with new interesting problems, and helps experts in physics and related fields to know more about ideas and tools from the modern control theory.},
  language  = {en}
}
@inproceedings{Puls2007,
  author    = {Puls, Joachim},
  title     = {Discussion : X-rays},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18000},
  year      = {2007},
  abstract  = {Clumping in hot-star winds : proceedings of an international workshop held in Potsdam, Germany, 18. - 22. June 2007},
  language  = {en}
}
@inproceedings{Szeifert2007,
  author    = {Szeifert, T.},
  title     = {Wind variabilities and asymmetries in Luminous Blue Variables},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18146},
  year      = {2007},
  abstract  = {Luminous Blue Variables show strong changes in their stellar wind on time scales of typically years to decades when they expand and contract radially at approximately constant luminosity. Micro-variability on shorter time scales and amplitudes can be observed superimposed to the larger scale radial changes. I will show long-term time series of high resolution spectra which we have collected in the past 20 years for many of the well known LBVs together with a few time series of weekly sampling (HR Car, R40, R71, R110, R127, S Dor) covering a time windows of up to a few months. Wind variability is seen on short and intermediate time scales with the line profiles changing from P Cygni to inverse P Cygni and double peeked profiles sometimes for the same star and spectral line. On longer time scales the ionisation levels for all chemical elements change drastically due to the strong change of the temperature on the stellar surface. While on the long term the characteristic radial changes may have impact on the over all mass loss rates, the variabilities and asymmetries on short and intermediate time scales may cause false estimates of the mass loss rates when confronting models with the observed line profiles},
  language  = {en}
}
@inproceedings{Moffat2007,
  author    = {Moffat, Anthony F. J.},
  title     = {Observational overview of clumping in hot stellar winds},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17633},
  year      = {2007},
  abstract  = {In the old days (pre ∼1990) hot stellar winds were assumed to be smooth, which made life fairly easy and bothered no one. Then after suspicious behaviour had been revealed, e.g. stochastic temporal variability in broadband polarimetry of single hot stars, it took the emerging CCD technology developed in the preceding decades (∼1970-80's) to reveal that these winds were far from smooth. It was mainly high-S/N, time-dependent spectroscopy of strong optical recombination emission lines in WR, and also a few OB and other stars with strong hot winds, that indicated all hot stellar winds likely to be pervaded by thousands of multiscale (compressible supersonic turbulent?) structures, whose driver is probably some kind of radiative instability. Quantitative estimates of clumping-independent mass-loss rates came from various fronts, mainly dependent directly on density (e.g. electron-scattering wings of emission lines, UV spectroscopy of weak resonance lines, and binary-star properties including orbital-period changes, electron-scattering, and X-ray fluxes from colliding winds) rather than the more common, easier-to-obtain but clumping-dependent density-squared diagnostics (e.g. free-free emission in the IR/radio and recombination lines, of which the favourite has always been Hα). Many big questions still remain, such as: What do the clumps really look like? Do clumping properties change as one recedes from the mother star? Is clumping universal? Does the relative clumping correction depend on \$\dot{M}\$ itself?},
  language  = {en}
}
@inproceedings{PulsMarkovaNajarroetal.2007,
  author    = {Puls, Joachim and Markova, N. and Najarro, F. and Hanson, M. M.},
  title     = {Clumping in O-star winds},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17683},
  year      = {2007},
  abstract  = {We review various diagnostics of clumping in O-star winds, with special emphasis on its radial stratification. Implications and problems are discussed, and promising NIR methods are presented.},
  language  = {en}
}
@inproceedings{StLouisMoffat2007,
  author    = {St-Louis, N. and Moffat, Anthony F. J.},
  title     = {Do clumping corrections increase with decreasing mass-loss rates?},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17696},
  year      = {2007},
  abstract  = {We report on new mass-loss rate estimates for O stars in six massive binaries using the amplitude of orbital-phase dependent, linear-polarimetric variability caused by electron scattering off free electrons in the winds. Our estimated mass-loss rates for luminous O stars are independent of clumping. They suggest similar clumping corrections as for WR stars and do not support the recently proposed reduction in mass-loss rates of O stars by one or two orders of magnitude.},
  language  = {en}
}
@inproceedings{Smith2007,
  author    = {Smith, Nathan},
  title     = {Independent signs of lower mass-loss rates for O-type stars},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17659},
  year      = {2007},
  abstract  = {I discuss observational evidence - independent of the direct spectral diagnostics of stellar winds themselves - suggesting that mass-loss rates for O stars need to be revised downward by roughly a factor of three or more, in line with recent observed mass-loss rates for clumped winds. These independent constraints include the large observed mass-loss rates in LBV eruptions, the large masses of evolved massive stars like LBVs and WNH stars, WR stars in lower metallicity environments, observed rotation rates of massive stars at different metallicity, supernovae that seem to defy expectations of high mass-loss rates in stellar evolution, and other clues. I pay particular attention to the role of feedback that would result from higher mass-loss rates, driving the star to the Eddington limit too soon, and therefore making higher rates appear highly implausible. Some of these arguments by themselves may have more than one interpretation, but together they paint a consistent picture that steady line-driven winds of O-type stars have lower mass-loss rates and are significantly clumped.},
  language  = {en}
}
@inproceedings{VotrubaFeldmeierKubatetal.2007,
  author    = {Votruba, V. and Feldmeier, Achim and Kub{\´a}t, Jiř{\´i} and R{\"a}tzel, D.},
  title     = {Multicomponent stellar wind of hot stars},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17677},
  year      = {2007},
  abstract  = {We developed a time-dependent multicomponent hydrodynamical code for simulation of the stellar wind from hot stars and applied it to stars with high and low density winds.},
  language  = {en}
}
@inproceedings{Lobel2007,
  author    = {Lobel, A.},
  title     = {Modeling DACs in UV lines of massive hot stars},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17856},
  year      = {2007},
  abstract  = {We apply the 3-dimensional radiative transport codeWind3D to 3D hydrodynamic models of Corotating Interaction Regions to fit the detailed variability of Discrete Absorption Components observed in Si iv UV resonance lines of HD 64760 (B0.5 Ib). We discuss important effects of the hydrodynamic input parameters on these large-scale equatorial wind structures that determine the detailed morphology of the DACs computed with 3D transfer. The best fit model reveals that the CIR in HD 64760 is produced by a source at the base of the wind that lags behind the stellar surface rotation. The non-corotating coherent wind structure is an extended density wave produced by a local increase of only 0.6\% in the smooth symmetric wind mass-loss rate.},
  language  = {en}
}
@inproceedings{PrinjaHodgesMassaetal.2007,
  author    = {Prinja, R. K. and Hodges, S. E. and Massa, D. L. and Fullerton, A. W. and Burnley, A. W.},
  title     = {Structure in the fast wind of NGC6543},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17788},
  year      = {2007},
  abstract  = {We exploit time-series \$FUSE\$ spectroscopy to {\it uniquely} probe spatial structure and clumping in the fast wind of the central star of the H-rich planetary nebula NGC~6543 (HD~164963). Episodic and recurrent optical depth enhancements are discovered in the P{\sc v} absorption troughs, with some evidence for a \$\sim\$ 0.17-day modulation time-scale. The characteristics of these features are essentially identical to the discrete absorption components' (DACs) commonly seen in the UV lines of massive OB stars, suggesting the temporal structures seen in NGC~6543 likely have a physical origin that is similar to that operating in massive, luminous stars. The mechanism for forming coherent perturbations in the outflows is therefore apparently operating equally in the radiation-pressure-driven winds of widely differing momenta (\$\mdot\$\$v_\infty\$\$R_\star^{0.5}\$) and flow times, as represented by OB stars and CSPN.},
  language  = {en}
}
@inproceedings{Marchenko2007,
  author    = {Marchenko, S. V.},
  title     = {Wind inhomogeneities in low-Z environment : observations},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17769},
  year      = {2007},
  abstract  = {We discuss the results of time-resolved spectroscopy of three presumably single Population I Wolf-Rayet stars in the Small Magellanic Cloud, where the ambient metallicity is \$\sim 1/5 Z_\odot\$. We were able to detect and follow numerous small-scale wind-embedded inhomogeneities in all observed stars. The general properties of the moving features, such as their velocity dispersions, emissivities and average accelerations, closely match the corresponding characteristics of small-scale inhomogeneities in the winds of Galactic Wolf-Rayet stars.},
  language  = {en}
}
@inproceedings{NajarroPulsHerreroetal.2007,
  author    = {Najarro, F. and Puls, Joachim and Herrero, A. and Hanson, M. M. and Mart{\´i}n-Pintado, J. and Hillier, D. J.},
  title     = {Tracking the Clumping in OB Stars from UV to radio},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17701},
  year      = {2007},
  abstract  = {We review different line and continua diagnostics from the UV to radio, which can be utilized to simultaneously constrain the clumping structure throughout the stellar wind of massive OB stars.},
  language  = {en}
}
@inproceedings{Massa2007,
  author    = {Massa, D. L.},
  title     = {Discussion: Spectroscopy and Mass-Loss Diagnostics},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17821},
  year      = {2007},
  language  = {en}
}
@inproceedings{LiermannHamann2007,
  author    = {Liermann, A. and Hamann, Wolf-Rainer},
  title     = {Clumping in Galactic WN stars : a comparison of mass loss rates from UV/optical \& radio diagnostics},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17816},
  year      = {2007},
  abstract  = {The mass loss rates and other parameters for a large sample of Galactic WN stars have been revised by Hamann et al. (2006), using the most up-to date Potsdam Wolf-Rayet (PoWR) model atmospheres. For a sub-sample of these stars exist measurements of their radio free-free emission. After harmonizing the adopted distance and terminal wind velocities, we compare the mass loss rates obtained from the two diagnostics. The differences are discussed as a possible consequence of different clumping contrast in the line-forming and radio-emitting regions.},
  language  = {en}
}
@inproceedings{RaassenHuchtMilleretal.2007,
  author    = {Raassen, A. J. J. and Hucht, K. A. van der and Miller, N. A. and Cassinelli, Joseph P.},
  title     = {XMM-Newton observations of zeta Orionis (O9.7 Ib) : a collisional ionization equilibrium model},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17747},
  year      = {2007},
  abstract  = {We present the analysis of XMM-Newton observations of ζ Orionis. The analysis is based on fitting to the total spectrum as well as diagnostics of individual line.},
  language  = {en}
}
@inproceedings{IgnaceGayley2007,
  author    = {Ignace, R. and Gayley, K. G.},
  title     = {Circumstellar Magnetic Field Diagnostics from Line Polarization},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18066},
  year      = {2007},
  language  = {en}
}
@inproceedings{WalterZuritaHerasLeyder2007,
  author    = {Walter, R. and Zurita-Heras, J. and Leyder, J.-C.},
  title     = {Probing clumpy stellar winds with a neutron star},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18024},
  year      = {2007},
  abstract  = {INTEGRAL tripled the number of super-giant high-mass X-ray binaries (sgHMXB) known in the Galaxy by revealing absorbed and fast transient (SFXT) systems. Quantitative constraints on the wind clumping of massive stars can be obtained from the study of the hard X-ray variability of SFXT. A large fraction of the hard X-ray emission is emitted in the form of flares with a typical duration of 3 ksec, frequency of 7 days and luminosity of \$10^{36}\$ erg/s. Such flares are most probably emitted by the interaction of a compact object orbiting at \$\sim10~R_*\$ with wind clumps (\$10^{22 ... 23}\$ g) representing a large fraction of the stellar mass-loss rate. The density ratio between the clumps and the inter-clump medium is \$10^{2 ... 4}\$. The parameters of the clumps and of the inter-clump medium, derived from the SFXT flaring behavior, are in good agreement with macro-clumping scenario and line-driven instability simulations. SFXT are likely to have larger orbital radius than classical sgHMXB.},
  language  = {en}
}
@inproceedings{CassinelliIgnaceWaldronetal.2007,
  author    = {Cassinelli, Joseph P. and Ignace, R. and Waldron, W. and Cho, J. and Murphy, N. and Lazarian, A.},
  title     = {X-ray line emission produced in clump bow shocks},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18057},
  year      = {2007},
  abstract  = {We summarize Chandra observations of the emission line profiles from 17 OB stars. The lines tend to be broad and unshifted. The forbidden/intercombination line ratios arising from Helium-like ions provide radial distance information for the X-ray emission sources, while the H-like to He-like line ratios provide X-ray temperatures, and thus also source temperature versus radius distributions. OB stars usually show power law differential emission measure distributions versus temperature. In models of bow shocks, we find a power law differential emission measure, a wide range of ion stages, and the bow shock flow around the clumps provides transverse velocities comparable to HWHM values. We find that the bow shock results for the line profile properties, consistent with the observations of X-ray line emission for a broad range of OB star properties.},
  language  = {en}
}
@inproceedings{Runacres2007,
  author    = {Runacres, M. C.},
  title     = {Hydrodynamical models of clumping beyond 50 R∗},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18030},
  year      = {2007},
  abstract  = {We present one-dimensional, time-dependent models of the clumps generated by the linedeshadowing instability. In order to follow the clumps out to distances of more than 1000 R∗, we use an efficient moving-box technique. We show that, within the approximations, the wind can remain clumped well into the formation region of the radio continuum.},
  language  = {en}
}
@inproceedings{SchnerrHenrichs2007,
  author    = {Schnerr, R. S. and Henrichs, H. F.},
  title     = {Magnetic fields and wind variability in massive stars},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18075},
  year      = {2007},
  abstract  = {This paper describes the thesis work of Schnerr (2007) entitled "Magnetic fields and mass loss in massive stars", which aimed at a better understanding of the impact of magnetic fields on the winds of massive stars.},
  language  = {en}
}
@inproceedings{LeuteneggerCohenKahnetal.2007,
  author    = {Leutenegger, M. A. and Cohen, David H. and Kahn, S. M. and Owocki, S. P. and Paerels, F. B. S.},
  title     = {Resonance scattering in the X-ray emission lines profiles of ζ Puppis},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18085},
  year      = {2007},
  abstract  = {We present XMM-Newton Reflection Grating Spectrometer observations of pairs of X-ray emission line profiles from the O star ζ Pup that originate from the same He-like ion. The two profiles in each pair have different shapes and cannot both be consistently fit by models assuming the same wind parameters. We show that the differences in profile shape can be accounted for in a model including the effects of resonance scattering, which affects the resonance line in the pair but not the intercombination line. This implies that resonance scattering is also important in single resonance lines, where its effect is difficult to distinguish from a low effective continuum optical depth in the wind. Thus, resonance scattering may help reconcile X-ray line profile shapes with literature mass-loss rates.},
  language  = {en}
}
@inproceedings{MassaPrinjaFullerton2007,
  author    = {Massa, D. L. and Prinja, R. K. and Fullerton, A. W.},
  title     = {The effects of clumping on wind line variability},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18095},
  year      = {2007},
  abstract  = {We review the effects of clumping on the profiles of resonance doublets. By allowing the ratio of the doublet oscillator strenghts to be a free parameter, we demonstrate that doublet profiles contain more information than is normally utilized. In clumped (or porous) winds, this ratio can lies between unity and the ratio of the f-values, and can change as a function of velocity and time, depending on the fraction of the stellar disk that is covered by material moving at a particular velocity at a given moment. Using these insights, we present the results of SEI modeling of a sample of B supergiants, ζ Pup and a time series for a star whose terminal velocity is low enough to make the components of its Si VIλλ1400 independent. These results are interpreted within the framewrok of the Oskinova et al. (2007) model, and demonstrate how the doublet profiles can be used to extract infromation about wind structure.},
  language  = {en}
}
@inproceedings{Vink2007,
  author    = {Vink, J. S.},
  title     = {Discussion: Hydrodynamic modeling},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18046},
  year      = {2007},
  language  = {en}
}
@inproceedings{Hillier2007,
  author    = {Hillier, D. J.},
  title     = {On the influence of clumping on O and Wolf-Rayet spectra},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17903},
  year      = {2007},
  abstract  = {Overwhelming observational and theoretical evidence suggests that the winds of massive stars are highly clumped. We briefly discuss the influence of clumping on model diagnostics and the difficulties of allowing for the influence of clumping on model spectra. Because of its simplicity, and because of computational ease, most spectroscopic analyses incorporate clumping using the volume filling factor. The biases introduced by this approach are uncertain. To investigate alternative clumping models, and to help determine the validity of parameters derived using the volume filling factor method, we discuss results derived using an alternative model in which we assume that the wind is composed of optically thick shells.},
  language  = {en}
}
@inproceedings{Fullerton2007,
  author    = {Fullerton, A. W.},
  title     = {Discussion: Spectral modeling},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17917},
  year      = {2007},
  language  = {en}
}
@inproceedings{Townsend2007,
  author    = {Townsend, R. H. D.},
  title     = {Techniques for simulating radiative transfer through porous media},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17866},
  year      = {2007},
  abstract  = {In this contribution, I discuss some basic techniques that can be used to simulate radiative transfer through porous media. As specific examples, I consider scattering transfer through a clumped slab, and X-ray emission line formation in a clumped wind.},
  language  = {en}
}
@inproceedings{udDoula2007,
  author    = {ud-Doula, A.},
  title     = {Large-scale wind structure due to magnetic fields},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18010},
  year      = {2007},
  abstract  = {Magnetic fields influence the dynamics of hot-star winds and create large scale structure. Based on numerical magnetohydrodynamic (MHD) simulations, we model the wind of θ¹ Ori C, and then use the SEI method to compute synthetic line profiles for a range of viewing angles as function of rotational phase. The resulting dynamic spectrum for a moderately strong line shows a distinct modulation, but with a phase that seems at odds with available observations.},
  language  = {en}
}
@inproceedings{IpingSonnebornMassaetal.2007,
  author    = {Iping, R.C. and Sonneborn, G. and Massa, D.L. and Gies, D. and Williams, Simon E.},
  title     = {Far-ultraviolet spectroscopy of O+O binaries in the Magellanic Clouds},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17896},
  year      = {2007},
  abstract  = {We report FUSE observations in 2005-2006 of three O-type, double-lined spectroscopic binaries in the Magellanic Clouds. The systems have very short periods (1.4-2.25 d), represent rare, young evolutionary stages of massive stars and binaries, and provide a unique glimpse at some of the most massive systems that form in dense clusters of massive stars. Improved orbit parameters, including revised masses, for LH54-425 are derived from new ctio spectroscopy. The systems are: LH54-425 in the LMC (O3V + O5V, P=2.25d, 62+37M⊙), J053441-693139 in the LMC (O2-3If+O6V, P=1.4 d, 41+27M⊙), and Hodge 53-47 in the SMC (O6V + O4-5IIIf, P=2.2 d, 24+14M⊙, where the O4 star appears to be less massive than the O6 star). Their short periods indicates that wind interaction and mass transfer are likely important factors in their evolution. The spectra provide quantitative and systematic studies of phase-dependent stellar wind properties, wind collision effects in O+O binaries at lower metallicities, improved radial velocity curves, and FUV spectro-photometric changes as a function of orbital phase.},
  language  = {en}
}
@inproceedings{KustererNagelWerneretal.2007,
  author    = {Kusterer, D.-J. and Nagel, T. and Werner, K. and Feldmeier, Achim},
  title     = {Radiative transfer in CV disk winds},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17847},
  year      = {2007},
  abstract  = {Mass accretion onto compact objects through accretion disks is a common phenomenon in the universe. It is seen in all energy domains from active galactic nuclei through cataclysmic variables (CVs) to young stellar objects. Because CVs are fairly easy to observe, they provide an ideal opportunity to study accretion disks in great detail and thus help us to understand accretion also in other energy ranges. Mass accretion in these objects is often accompanied by mass outflow from the disks. This accretion disk wind, at least in CVs, is thought to be radiatively driven, similar to O star winds. WOMPAT, a 3-D Monte Carlo radiative transfer code for accretion disk winds of CVs is presented.},
  language  = {en}
}
@inproceedings{DaviesVinkOudmaijer2007,
  author    = {Davies, B. and Vink, J. S. and Oudmaijer, R. D.},
  title     = {Modelling the polarimetric variability of hot stars},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17939},
  year      = {2007},
  abstract  = {Many hot stars exhibit stochastic polarimetric variability, thought to arise from clumping low in the wind. Here we investigate the wind properties required to reproduce this variability using analytic models, with particular emphasis on Luminous Blue Variables. We find that the winds must be highly structured, consisting of a large number of optically-thin clumps; while we find that the overall level of polarization should scale with mass-loss rate - consistent with observations of LBVs. The models also predict variability on very short timescales, which is supported by the results of a recent polarimetric monitoring campaign.},
  language  = {en}
}
@inproceedings{KubatSaad2007,
  author    = {Kub{\´a}t, Jiř{\´i} and Saad, S. M.},
  title     = {Moving absorption bumps in the spectra of Be stars},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17879},
  year      = {2007},
  abstract  = {Several Be binaries exhibit an absorption bump moving across the blue wing of hydrogen emission lines towards the line center. This bump is demonstrated for the case of two bright Be stars, κ Dra and 4 Her. It is not clear what is the reason for this travelling bump.},
  language  = {en}
}
@inproceedings{Nielsen2007,
  author    = {Nielsen, K. E.},
  title     = {On irregular line profiles in the optical spectrum of Eta Carinae},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18227},
  year      = {2007},
  abstract  = {The optical spectrum of Eta Carinae (η Car) is prominent in H I, He i and Fe ii wind lines, all of which vary both in absorption and emission with phase. The phase dependance is a consequence of the interaction between the two objects in the η Car binary (η Car A \& B). The binary system is enshrouded by ejecta from previous mass ejection events and consequently, η Car B is not directly observable. We have traced the He i lines over η Car's spectroscopic period, using HST/STIS data obtained with medium spectral, but high angular, resolving power, and created a radial velocity curve for the system. The He I lines are formed in the core of the system, and appear to be a composite of multiple features formed in spatially separated regions. The sources of their irregular line profiles are still not fully understood, but can be attributed to emission/absorption near the wind-wind interface and/or a direct consequence of the η Car A's, massive, clumpy wind. This paper will discuss the spectral variability, the narrow emission structure of the He i lines and how clumpiness of the winds may impede the construction of the reliable radial velocity curve, necessary for characterizations of especially η Car B.},
  language  = {en}
}
@inproceedings{CohenLeuteneggerTownsend2007,
  author    = {Cohen, David H. and Leutenegger, M. A. and Townsend, R. H. D.},
  title     = {Quantitative analysis of resolved X-ray emission line profiles of O stars},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18115},
  year      = {2007},
  abstract  = {By quantitatively fitting simple emission line profile models that include both atomic opacity and porosity to the Chandra X-ray spectrum of ζ Pup, we are able to explore the trade-offs between reduced mass-loss rates and wind porosity. We find that reducing the mass-loss rate of ζ Pup by roughly a factor of four, to 1.5 × 10-6 M⊙ yr-1, enables simple non-porous wind models to provide good fits to the data. If, on the other hand, we take the literature mass-loss rate of 6×10-6 M⊙ yr-1, then to produce X-ray line profiles that fit the data, extreme porosity lengths - of h∞ ≈ 3 R∗ - are required. Moreover, these porous models do not provide better fits to the data than the non-porous, low optical depth models. Additionally, such huge porosity lengths do not seem realistic in light of 2-D numerical simulations of the wind instability.},
  language  = {en}
}
@inproceedings{MorrisonRotherKurschat2007,
  author    = {Morrison, N. D. and Rother, R. and Kurschat, N.},
  title     = {Hα line profile variability in the B8Ia-type supergiant Rigel (β Ori)},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18120},
  year      = {2007},
  abstract  = {Hα observations of Rigel obtained on 184 nights during the past ten years with the 1-m telescope and ´echelle spectrograph of Ritter Observatory are surveyed. The line profiles were classified in terms of morphology. About 1/4 of them are of P Cygni type, about 15\% inverse P Cygni, about 25\% double-peaked, about 1/3 pure absorption, and a few are single emission lines. Transformation of the profile from one type to another typically takes a few days. Although the line stays in absorption for extended intervals, only one high-velocity absorption event of the intensity reported by Kaufer et al. (1996a) was observed, in late 2006. Late in this event, Hα absorption occurred farther to the red than the red wing of a plausible photospheric absorption component, an indication of infalling material. In general, as the absorption events come to an end, the emission typically returns with an inverse P Cygni profile. The Hα profile class shows no obvious correlation with the radial velocity of C II λ6578, a photospheric absorption line.},
  language  = {en}
}
@inproceedings{CheneMoffatCrowther2007,
  author    = {Chen{\´e}, A.-N. and Moffat, Anthony F. J. and Crowther, P. A.},
  title     = {Rapidly accelerating clumps in the winds of the very hot WNE Stars},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18163},
  year      = {2007},
  abstract  = {We study the time variability of emission lines in three WNE stars : WR 2 (WN2), WR 3 (WN3ha) and WR152 (WN3). While WR 2 shows no variability above the noise level, the other stars do show variation, which are like other WR stars in WR 152 but very fast in WR 3. From these motions, we deduce a value of β ∼1 for WR 3 that is like that seen in O stars and β ∼2-3 for WR 152, that is intermediate between other WR stars and WR 3.},
  language  = {en}
}
@inproceedings{Kholtygin2007,
  author    = {Kholtygin, A. F.},
  title     = {Modelling the induced clumping stochastic line profile variability},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18180},
  year      = {2007},
  abstract  = {We model the line profile variability (lpv) in spectra of clumped stellar atmospheres using the Stochastic Clump Model (SCM) of the winds of early-type stars. In this model the formation of dense inhomogeneities (clumps) in the line driven winds is considered as being a stochastic process. It is supposed that the emission due to clumps mainly contributes to the intensities of emission lines in the stellar spectra. It is shown that in the framework of the SCM it is possible to reproduce both the mean line profiles and a common pattern of the lpv.},
  language  = {en}
}
@inproceedings{Cassinelli2007,
  author    = {Cassinelli, Joseph P.},
  title     = {Discussion: Magnetic fields, variability},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18195},
  year      = {2007},
  language  = {en}
}
@inproceedings{StLouis2007,
  author    = {St-Louis, N.},
  title     = {Discussion: Binaries, colliding winds, LBVs and high energy radiation},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18155},
  year      = {2007},
  abstract  = {Clumping in hot-star winds : proceedings of an international workshop held in Potsdam, Germany, 18. - 22. June 2007},
  language  = {en}
}
@inproceedings{RomeroOwockiAraudoetal.2007,
  author    = {Romero, G. E. and Owocki, S. P. and Araudo, A. T. and Townsend, R. H. D. and Benaglia, P.},
  title     = {Using gamma-rays to probe the clumped structure of stellar winds},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18210},
  year      = {2007},
  abstract  = {Gamma-rays can be produced by the interaction of a relativistic jet and the matter of the stellar wind in the subclass of massive X-ray binaries known as "microquasars". The relativistic jet is ejected from the surroundings of the compact object and interacts with cold protons from the stellar wind, producing pions that then quickly decay into gamma-rays. Since the resulting gamma-ray emissivity depends on the target density, the detection of rapid variability in microquasars with GLAST and the new generation of Cherenkov imaging arrays could be used to probe the clumped structure of the stellar wind. In particular, we show here that the relative fluctuation in gamma rays may scale with the square root of the ratio of porosity length to binary separation, \$\sqrt{h/a}\$, implying for example a ca. 10\% variation in gamma ray emission for a quite moderate porosity, h/a ∼ 0.01.},
  language  = {en}
}
@inproceedings{Weis2007,
  author    = {Weis, K.},
  title     = {Wind relics : clumps, inhomogeneities and outflows in LBV nebulae},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-18235},
  year      = {2007},
  abstract  = {The most massive stars are those with the shortest but most active life. One group of massive stars, the Luminous Blue Variables (LBVs), of which only a few objects are known, are in particular of interest concerning the stability of stars. They have a high mass loss rate and are close to being instable. This is even more likely as rotation becomes an important factor in stellar evolution of these stars. Through massive stellar winds and sometimes giant eruptions, LBV nebulae are formed. Various aspects in the evolution in the LBV phase lead, beside the large scale morphological and kinematical differences, to a diversity of small structures like clumps, rims, and outflows in these nebulae.},
  language  = {en}
}
@inproceedings{KrtičkaPulsKubat2007,
  author    = {Krtička, Jiri and Puls, Joachim and Kub{\´a}t, Jiř{\´i}},
  title     = {The influence of clumping on predicted O star wind parameters},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17969},
  year      = {2007},
  abstract  = {We study the influence of clumping on the predicted wind structure of O-type stars. For this purpose we artificially include clumping into our stationary wind models. When the clumps are assumed to be optically thin, the radiative line force increases compared to corresponding unclumped models, with a similar effect on either the mass-loss rate or the terminal velocity (depending on the onset of clumping). Optically thick clumps, alternatively, might be able to decrease the radiative force.},
  language  = {en}
}
@inproceedings{KrausKubatKrtička2007,
  author    = {Kraus, M. and Kub{\´a}t, Jiř{\´i} and Krtička, Jiri},
  title     = {Wind emission of OB supergiants and the influence of clumping},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-17757},
  year      = {2007},
  abstract  = {The influence of the wind to the total continuum of OB supergiants is discussed. For wind velocity distributions with β > 1.0, the wind can have strong influence to the total continuum emission, even at optical wavelengths. Comparing the continuum emission of clumped and unclumped winds, especially for stars with high β values, delivers flux differences of up to 30\% with maximum in the near-IR. Continuum observations at these wavelengths are therefore an ideal tool to discriminate between clumped and unclumped winds of OB supergiants.},
  language  = {en}
}
@inproceedings{Piskorski2008,
  author    = {Piskorski, Jakub},
  title     = {ExPRESS : extraction pattern recognition engine and specification suite},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27227},
  year      = {2008},
  abstract  = {The emergence of information extraction (IE) oriented pattern engines has been observed during the last decade. Most of them exploit heavily finite-state devices. This paper introduces ExPRESS - a new extraction pattern engine, whose rules are regular expressions over flat feature structures. The underlying pattern language is a blend of two previously introduced IE oriented pattern formalisms, namely, JAPE, used in the widely known GATE system, and the unificationbased XTDL formalism used in SProUT. A brief and technical overview of ExPRESS, its pattern language and the pool of its native linguistic components is given. Furthermore, the implementation of the grammar interpreter is addressed too.},
  language  = {en}
}
@inproceedings{Watson2008,
  author    = {Watson, Bruce W.},
  title     = {Advances in automata implementation techniques (Abstract)},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27094},
  year      = {2008},
  language  = {en}
}
@inproceedings{Barthelemy2008,
  author    = {Barth{\´e}lemy, Fran{\c{c}}ois},
  title     = {Finite-state compilation of feature structures for two-level morphology},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27120},
  year      = {2008},
  abstract  = {This paper describes a two-level formalism where feature structures are used in contextual rules. Whereas usual two-level grammars describe rational sets over symbol pairs, this new formalism uses tree structured regular expressions. They allow an explicit and precise definition of the scope of feature structures. A given surface form may be described using several feature structures. Feature unification is expressed in contextual rules using variables, like in a unification grammar. Grammars are compiled in finite state multi-tape transducers.},
  language  = {en}
}
@inproceedings{BlancConstantWatrin2008,
  author    = {Blanc, Olivier and Constant, Matthieu and Watrin, Patrick},
  title     = {Segmentation in super-chunks with a finite-state approach},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27133},
  year      = {2008},
  abstract  = {Since Harris' parser in the late 50s, multiword units have been progressively integrated in parsers. Nevertheless, in the most part, they are still restricted to compound words, that are more stable and less numerous. Actually, language is full of semi-fixed expressions that also form basic semantic units: semi-fixed adverbial expressions (e.g. time), collocations. Like compounds, the identification of these structures limits the combinatorial complexity induced by lexical ambiguity. In this paper, we detail an experiment that largely integrates these notions in a finite-state procedure of segmentation into super-chunks, preliminary to a parser.We show that the chunker, developped for French, reaches 92.9\% precision and 98.7\% recall. Moreover, multiword units realize 36.6\% of the attachments within nominal and prepositional phrases.},
  language  = {en}
}
@inproceedings{BonfanteLeRoux2008,
  author    = {Bonfante, Guillaume and Le Roux, Joseph},
  title     = {Intersection optimization is NP-complete},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27146},
  year      = {2008},
  abstract  = {Finite state methods for natural language processing often require the construction and the intersection of several automata. In this paper, we investigate the question of determining the best order in which these intersections should be performed. We take as an example lexical disambiguation in polarity grammars. We show that there is no efficient way to minimize the state complexity of these intersections.},
  language  = {en}
}
@inproceedings{Daciuk2008,
  author    = {Daciuk, Jan},
  title     = {Perfect hashing tree automata},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27163},
  year      = {2008},
  abstract  = {We present an algorithm that computes a function that assigns consecutive integers to trees recognized by a deterministic, acyclic, finite-state, bottom-up tree automaton. Such function is called minimal perfect hashing. It can be used to identify trees recognized by the automaton. Its value may be seen as an index in some other data structures. We also present an algorithm for inverted hashing.},
  language  = {en}
}
@inproceedings{PadroPadro2008,
  author    = {Padr{\´o}, Muntsa and Padr{\´o}, Llu{\´i}s},
  title     = {ME-CSSR : an extension of CSSR using maximum entropy models},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27210},
  year      = {2008},
  abstract  = {In this work an extension of CSSR algorithm using Maximum Entropy Models is introduced. Preliminary experiments to perform Named Entity Recognition with this new system are presented.},
  language  = {en}
}
@inproceedings{BoegelButtHautlietal.2008,
  author    = {B{\"o}gel, Tina and Butt, Miriam and Hautli, Annette and Sulger, Sebastian},
  title     = {Developing a finite-state morphological analyzer for Urdu and Hindi},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27155},
  year      = {2008},
  abstract  = {We introduce and discuss a number of issues that arise in the process of building a finite-state morphological analyzer for Urdu, in particular issues with potential ambiguity and non-concatenative morphology. Our approach allows for an underlyingly similar treatment of both Urdu and Hindi via a cascade of finite-state transducers that transliterates the very different scripts into a common ASCII transcription system. As this transliteration system is based on the XFST tools that the Urdu/Hindi common morphological analyzer is also implemented in, no compatibility problems arise.},
  language  = {en}
}
@inproceedings{YliJyrae2008,
  author    = {Yli-Jyr{\"a}, Anssi},
  title     = {Applications of diamonded double negation},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27109},
  year      = {2008},
  abstract  = {Nested complementation plays an important role in expressing counter- i.e. star-free and first-order definable languages and their hierarchies. In addition, methods that compile phonological rules into finite-state networks use double-nested complementation or "double negation". This paper reviews how the double-nested complementation extends to a relatively new operation, generalized restriction (GR), coined by the author (Yli-Jyr{\"a} and Koskenniemi 2004). This operation encapsulates a double-nested complementation and elimination of a concatenation marker, diamond, whose finite occurrences align concatenations in the arguments of the operation. The paper demonstrates that the GR operation has an interesting potential in expressing regular languages, various kinds of grammars, bimorphisms and relations. This motivates a further study of optimized implementation of the operator.},
  language  = {en}
}
@inproceedings{BarbaianiCanceddaDanceetal.2008,
  author    = {Barbaiani, Mădălina and Cancedda, Nicola and Dance, Chris and Fazekas, Szil{\´a}rd and Ga{\´a}l, Tam{\´a}s and Gaussier, {\´E}ric},
  title     = {Asymmetric term alignment with selective contiguity constraints by multi-tape automata},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27115},
  year      = {2008},
  abstract  = {This article describes a HMM-based word-alignment method that can selectively enforce a contiguity constraint. This method has a direct application in the extraction of a bilingual terminological lexicon from a parallel corpus, but can also be used as a preliminary step for the extraction of phrase pairs in a Phrase-Based Statistical Machine Translation system. Contiguous source words composing terms are aligned to contiguous target language words. The HMM is transformed into a Weighted Finite State Transducer (WFST) and contiguity constraints are enforced by specific multi-tape WFSTs. The proposed method is especially suited when basic linguistic resources (morphological analyzer, part-of-speech taggers and term extractors) are available for the source language only.},
  language  = {en}
}
@inproceedings{Karttunen2008,
  author    = {Karttunen, Lauri},
  title     = {New features in PARC finite state toolkits (Abstract)},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27085},
  year      = {2008},
  language  = {en}
}
@inproceedings{YliJyrae2008,
  author    = {Yli-Jyr{\"a}, Anssi},
  title     = {Transducers from parallel replace rules and modes with generalized lenient composition},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27246},
  year      = {2008},
  abstract  = {Generalized Two-Level Grammar (GTWOL) provides a new method for compilation of parallel replacement rules into transducers. The current paper identifies the role of generalized lenient composition (GLC) in this method. Thanks to the GLC operation, the compilation method becomes bipartite and easily extendible to capture various application modes. In the light of three notions of obligatoriness, a modification to the compilation method is proposed. We argue that the bipartite design makes implementation of parallel obligatoriness, directionality, length and rank based application modes extremely easy, which is the main result of the paper.},
  language  = {en}
}
@inproceedings{Saleschus2008,
  author    = {Sal{\´e}schus, Dirk},
  title     = {On resolving long distance dependencies in Russian verbs},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27235},
  year      = {2008},
  abstract  = {Morphological analyses based on word syntax approaches can encounter difficulties with long distance dependencies. The reason is that in some cases an affix has to have access to the inner structure of the form with which it combines. One solution is the percolation of features from ther inner morphemes to the outer morphemes with some process of feature unification. However, the obstacle of percolation constraints or stipulated features has lead some linguists to argue in favour of other frameworks such as, e.g., realizational morphology or parallel approaches like optimality theory. This paper proposes a linguistic analysis of two long distance dependencies in the morphology of Russian verbs, namely secondary imperfectivization and deverbal nominalization.We show how these processes can be reanalysed as local dependencies. Although finitestate frameworks are not bound by such linguistically motivated considerations, we present an implementation of our analysis as proposed in [1] that does not complicate the grammar or enlarge the network unproportionally.},
  language  = {en}
}
@inproceedings{IlarrazaGojenolaOronozetal.2008,
  author    = {Ilarraza, Arantza D{\´i}az de and Gojenola, Koldo and Oronoz, Maite and Otaegi, Maialen and Alegria, I{\~n}aki},
  title     = {Syntactic error detection and correction in date expressions using finite-state transducers},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27180},
  year      = {2008},
  abstract  = {This paper presents a system for the detection and correction of syntactic errors. It combines a robust morphosyntactic analyser and two groups of finite-state transducers specified using the Xerox Finite State Tool (xfst). One of the groups is used for the description of syntactic error patterns while the second one is used for the correction of the detected errors. The system has been tested on a corpus of real texts, containing both correct and incorrect sentences, with good results.},
  language  = {en}
}
@inproceedings{Fernando2008,
  author    = {Fernando, Tim},
  title     = {Temporal propositions as regular languages},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27194},
  year      = {2008},
  abstract  = {Temporal propositions are mapped to sets of strings that witness (in a precise sense) the propositions over discrete linear Kripke frames. The strings are collected into regular languages to ensure the decidability of entailments given by inclusions between languages. (Various notions of bounded entailment are shown to be expressible as language inclusions.) The languages unwind computations implicit in the logical (and temporal) connectives via a system of finite-state constraints adapted from finite-state morphology. Applications to Hybrid Logic and non-monotonic inertial reasoning are briefly considered.},
  language  = {en}
}
@inproceedings{Didakowski2008,
  author    = {Didakowski, J{\"o}rg},
  title     = {SynCoP : combining syntactic tagging with chunking using weighted finite state transducers},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27172},
  year      = {2008},
  abstract  = {This paper describes the key aspects of the system SynCoP (Syntactic Constraint Parser) developed at the Berlin-Brandenburgische Akademie der Wissenschaften. The parser allows to combine syntactic tagging and chunking by means of constraint grammar using weighted finite state transducers (WFST). Chunks are interpreted as local dependency structures within syntactic tagging. The linguistic theories are formulated by criteria which are formalized by a semiring; these criteria allow structural preferences and gradual grammaticality. The parser is essentially a cascade of WFSTs. To find the most likely syntactic readings a best-path search is used.},
  language  = {en}
}
@inproceedings{ZarriessSeeker2008,
  author    = {Zarrieß, Sina and Seeker, Wolfgang},
  title     = {Finite-state rule deduction for parsing non-constituent coordination},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27254},
  year      = {2008},
  abstract  = {In this paper, we present a finite-state approach to constituency and therewith an analysis of coordination phenomena involving so-called non-constituents. We show that non-constituents can be seen as parts of fully-fledged constituents and therefore be coordinated in the same way. We have implemented an algorithm based on finite state automata that generates an LFG grammar assigning valid analyses to non-constituent coordination structures in the German language.},
  language  = {en}
}
@inproceedings{GonzalezCasacuberta2008,
  author    = {Gonz{\´a}lez, Jorge and Casacuberta, Francisco},
  title     = {Phrase-based finite state models},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-27209},
  year      = {2008},
  abstract  = {In the last years, statistical machine translation has already demonstrated its usefulness within a wide variety of translation applications. In this line, phrase-based alignment models have become the reference to follow in order to build competitive systems. Finite state models are always an interesting framework because there are well-known efficient algorithms for their representation and manipulation. This document is a contribution to the evolution of finite state models towards a phrase-based approach. The inference of stochastic transducers that are based on bilingual phrases is carefully analysed from a finite state point of view. Indeed, the algorithmic phenomena that have to be taken into account in order to deal with such phrase-based finite state models when in decoding time are also in-depth detailed.},
  language  = {en}
}
@inproceedings{BandaGallagher2010,
  author    = {Banda, Gourinath and Gallagher, John P.},
  title     = {Constraint-based abstraction of a model checker for infinite state systems},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41516},
  year      = {2010},
  abstract  = {Abstract interpretation-based model checking provides an approach to verifying properties of infinite-state systems. In practice, most previous work on abstract model checking is either restricted to verifying universal properties, or develops special techniques for temporal logics such as modal transition systems or other dual transition systems. By contrast we apply completely standard techniques for constructing abstract interpretations to the abstraction of a CTL semantic function, without restricting the kind of properties that can be verified. Furthermore we show that this leads directly to implementation of abstract model checking algorithms for abstract domains based on constraints, making use of an SMT solver.},
  language  = {en}
}
@inproceedings{GoltzPieth2010,
  author    = {Goltz, Hans-Joachim and Pieth, Norbert},
  title     = {A tool for generating partition schedules of multiprocessor systems},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41556},
  year      = {2010},
  abstract  = {A deterministic cycle scheduling of partitions at the operating system level is supposed for a multiprocessor system. In this paper, we propose a tool for generating such schedules. We use constraint based programming and develop methods and concepts for a combined interactive and automatic partition scheduling system. This paper is also devoted to basic methods and techniques for modeling and solving this partition scheduling problem. Initial application of our partition scheduling tool has proved successful and demonstrated the suitability of the methods used.},
  language  = {en}
}
@inproceedings{Schrijvers2010,
  author    = {Schrijvers, Tom},
  title     = {Overview of the monadic constraint programming framework},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41411},
  year      = {2010},
  abstract  = {A constraint programming system combines two essential components: a constraint solver and a search engine. The constraint solver reasons about satisfiability of conjunctions of constraints, and the search engine controls the search for solutions by iteratively exploring a disjunctive search tree defined by the constraint program. The Monadic Constraint Programming framework gives a monadic definition of constraint programming where the solver is defined as a monad threaded through the monadic search tree. Search and search strategies can then be defined as firstclass objects that can themselves be built or extended by composable search transformers. Search transformers give a powerful and unifying approach to viewing search in constraint programming, and the resulting constraint programming system is first class and extremely flexible.},
  language  = {en}
}
@inproceedings{HerreHummel2010,
  author    = {Herre, Heinrich and Hummel, Axel},
  title     = {Stationary generated models of generalized logic programs},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41501},
  year      = {2010},
  abstract  = {The interest in extensions of the logic programming paradigm beyond the class of normal logic programs is motivated by the need of an adequate representation and processing of knowledge. One of the most difficult problems in this area is to find an adequate declarative semantics for logic programs. In the present paper a general preference criterion is proposed that selects the 'intended' partial models of generalized logic programs which is a conservative extension of the stationary semantics for normal logic programs of [Prz91]. The presented preference criterion defines a partial model of a generalized logic program as intended if it is generated by a stationary chain. It turns out that the stationary generated models coincide with the stationary models on the class of normal logic programs. The general wellfounded semantics of such a program is defined as the set-theoretical intersection of its stationary generated models. For normal logic programs the general wellfounded semantics equals the wellfounded semantics.},
  language  = {en}
}
@inproceedings{AbdennadherIsmailKhoury2010,
  author    = {Abdennadher, Slim and Ismail, Haythem and Khoury, Frederick},
  title     = {Transforming imperative algorithms to constraint handling rules},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41533},
  year      = {2010},
  abstract  = {Different properties of programs, implemented in Constraint Handling Rules (CHR), have already been investigated. Proving these properties in CHR is fairly simpler than proving them in any type of imperative programming language, which triggered the proposal of a methodology to map imperative programs into equivalent CHR. The equivalence of both programs implies that if a property is satisfied for one, then it is satisfied for the other. The mapping methodology could be put to other beneficial uses. One such use is the automatic generation of global constraints, at an attempt to demonstrate the benefits of having a rule-based implementation for constraint solvers.},
  language  = {en}
}
@inproceedings{BetzRaiserFruehwirth2010,
  author    = {Betz, Hariolf and Raiser, Frank and Fr{\"u}hwirth, Thom},
  title     = {Persistent constraints in constraint handling rules},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41547},
  year      = {2010},
  abstract  = {In the most abstract definition of its operational semantics, the declarative and concurrent programming language CHR is trivially non-terminating for a significant class of programs. Common refinements of this definition, in closing the gap to real-world implementations, compromise on declarativity and/or concurrency. Building on recent work and the notion of persistent constraints, we introduce an operational semantics avoiding trivial non-termination without compromising on its essential features.},
  language  = {en}
}
@inproceedings{OetschSchwengererTompits2010,
  author    = {Oetsch, Johannes and Schwengerer, Martin and Tompits, Hans},
  title     = {Kato: a plagiarism-detection tool for answer-set programs},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41485},
  year      = {2010},
  abstract  = {We present the tool Kato which is, to the best of our knowledge, the first tool for plagiarism detection that is directly tailored for answer-set programming (ASP). Kato aims at finding similarities between (segments of) logic programs to help detecting cases of plagiarism. Currently, the tool is realised for DLV programs but it is designed to handle various logic-programming syntax versions. We review basic features and the underlying methodology of the tool.},
  language  = {en}
}
@inproceedings{Zhou2010,
  author    = {Zhou, Neng-Fa},
  title     = {What I have learned from all these solver competitions},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41431},
  year      = {2010},
  abstract  = {In this talk, I would like to share my experiences gained from participating in four CSP solver competitions and the second ASP solver competition. In particular, I'll talk about how various programming techniques can make huge differences in solving some of the benchmark problems used in the competitions. These techniques include global constraints, table constraints, and problem-specific propagators and labeling strategies for selecting variables and values. I'll present these techniques with experimental results from B-Prolog and other CLP(FD) systems.},
  language  = {en}
}
@inproceedings{HanusKoschnicke2010,
  author    = {Hanus, Michael and Koschnicke, Sven},
  title     = {An ER-based framework for declarative web programming},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41447},
  year      = {2010},
  abstract  = {We describe a framework to support the implementation of web-based systems to manipulate data stored in relational databases. Since the conceptual model of a relational database is often specified as an entity-relationship (ER) model, we propose to use the ER model to generate a complete implementation in the declarative programming language Curry. This implementation contains operations to create and manipulate entities of the data model, supports authentication, authorization, session handling, and the composition of individual operations to user processes. Furthermore and most important, the implementation ensures the consistency of the database w.r.t. the data dependencies specified in the ER model, i.e., updates initiated by the user cannot lead to an inconsistent state of the database. In order to generate a high-level declarative implementation that can be easily adapted to individual customer requirements, the framework exploits previous works on declarative database programming and web user interface construction in Curry.},
  language  = {en}
}
@inproceedings{GeskeWolf2010,
  author    = {Geske, Ulrich and Wolf, Armin},
  title     = {Preface},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41401},
  year      = {2010},
  abstract  = {The workshops on (constraint) logic programming (WLP) are the annual meeting of the Society of Logic Programming (GLP e.V.) and bring together researchers interested in logic programming, constraint programming, and related areas like databases, artificial intelligence and operations research. In this decade, previous workshops took place in Dresden (2008), W{\"u}rzburg (2007), Vienna (2006), Ulm (2005), Potsdam (2004), Dresden (2002), Kiel (2001), and W{\"u}rzburg (2000). Contributions to workshops deal with all theoretical, experimental, and application aspects of constraint programming (CP) and logic programming (LP), including foundations of constraint/ logic programming. Some of the special topics are constraint solving and optimization, extensions of functional logic programming, deductive databases, data mining, nonmonotonic reasoning, , interaction of CP/LP with other formalisms like agents, XML, JAVA, program analysis, program transformation, program verification, meta programming, parallelism and concurrency, answer set programming, implementation and software techniques (e.g., types, modularity, design patterns), applications (e.g., in production, environment, education, internet), constraint/logic programming for semantic web systems and applications, reasoning on the semantic web, data modelling for the web, semistructured data, and web query languages.},
  language  = {en}
}
@inproceedings{Cabalar2010,
  author    = {Cabalar, Pedro},
  title     = {Existential quantifiers in the rule body},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41476},
  year      = {2010},
  abstract  = {In this paper we consider a simple syntactic extension of Answer Set Programming (ASP) for dealing with (nested) existential quantifiers and double negation in the rule bodies, in a close way to the recent proposal RASPL-1. The semantics for this extension just resorts to Equilibrium Logic (or, equivalently, to the General Theory of Stable Models), which provides a logic-programming interpretation for any arbitrary theory in the syntax of Predicate Calculus. We present a translation of this syntactic class into standard logic programs with variables (either disjunctive or normal, depending on the input rule heads), as those allowed by current ASP solvers. The translation relies on the introduction of auxiliary predicates and the main result shows that it preserves strong equivalence modulo the original signature.},
  language  = {en}
}
@inproceedings{HerreHummel2010,
  author    = {Herre, Heinrich and Hummel, Axel},
  title     = {A paraconsistent semantics for generalized logic programs},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41496},
  year      = {2010},
  abstract  = {We propose a paraconsistent declarative semantics of possibly inconsistent generalized logic programs which allows for arbitrary formulas in the body and in the head of a rule (i.e. does not depend on the presence of any specific connective, such as negation(-as-failure), nor on any specific syntax of rules). For consistent generalized logic programs this semantics coincides with the stable generated models introduced in [HW97], and for normal logic programs it yields the stable models in the sense of [GL88].},
  language  = {en}
}
@inproceedings{Seipel2010,
  author    = {Seipel, Dietmar},
  title     = {Practical Applications of Extended Deductive Databases in DATALOG*},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41457},
  year      = {2010},
  abstract  = {A wide range of additional forward chaining applications could be realized with deductive databases, if their rule formalism, their immediate consequence operator, and their fixpoint iteration process would be more flexible. Deductive databases normally represent knowledge using stratified Datalog programs with default negation. But many practical applications of forward chaining require an extensible set of user-defined built-in predicates. Moreover, they often need function symbols for building complex data structures, and the stratified fixpoint iteration has to be extended by aggregation operations. We present an new language Datalog*, which extends Datalog by stratified meta-predicates (including default negation), function symbols, and user-defined built-in predicates, which are implemented and evaluated top-down in Prolog. All predicates are subject to the same backtracking mechanism. The bottom-up fixpoint iteration can aggregate the derived facts after each iteration based on user-defined Prolog predicates.},
  language  = {en}
}
@inproceedings{Brass2010,
  author    = {Brass, Stefan},
  title     = {Range restriction for general formulas},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41521},
  year      = {2010},
  abstract  = {Deductive databases need general formulas in rule bodies, not only conjuctions of literals. This is well known since the work of Lloyd and Topor about extended logic programming. Of course, formulas must be restricted in such a way that they can be effectively evaluated in finite time, and produce only a finite number of new tuples (in each iteration of the TP-operator: the fixpoint can still be infinite). It is also necessary to respect binding restrictions of built-in predicates: many of these predicates can be executed only when certain arguments are ground. Whereas for standard logic programming rules, questions of safety, allowedness, and range-restriction are relatively easy and well understood, the situation for general formulas is a bit more complicated. We give a syntactic analysis of formulas that guarantees the necessary properties.},
  language  = {en}
}
@inproceedings{GebserHinrichsSchaubetal.2010,
  author    = {Gebser, Martin and Hinrichs, Henrik and Schaub, Torsten and Thiele, Sven},
  title     = {xpanda: a (simple) preprocessor for adding multi-valued propositions to ASP},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-41466},
  year      = {2010},
  abstract  = {We introduce a simple approach extending the input language of Answer Set Programming (ASP) systems by multi-valued propositions. Our approach is implemented as a (prototypical) preprocessor translating logic programs with multi-valued propositions into logic programs with Boolean propositions only. Our translation is modular and heavily benefits from the expressive input language of ASP. The resulting approach, along with its implementation, allows for solving interesting constraint satisfaction problems in ASP, showing a good performance.},
  language  = {en}
}