toggle visibility Search & Display Options

Select All    Deselect All
 |   | 
Details
  Records Links
Author O. Fors; A. Richichi; Xavier Otazu; J. Nuñez edit  openurl
  Title A new wavelet-based approach for the automated treatment of large sets of lunar occultation data Type Journal
  Year 2008 Publication Astronomy and Astrohysics Abbreviated Journal  
  Volume 480 Issue Pages 297–304  
  Keywords  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area (up) Expedition Conference  
  Notes CIC Approved no  
  Call Number CAT @ cat @ FRO2008 Serial 934  
Permanent link to this record
 

 
Author Robert Benavente; Maria Vanrell; Ramon Baldrich edit  openurl
  Title Parametric Fuzzy Sets for Automatic Color Naming Type Journal
  Year 2008 Publication Journal of the Optical Society of America A Abbreviated Journal  
  Volume 25 Issue 10 Pages 2582–2593  
  Keywords  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area (up) Expedition Conference  
  Notes CIC Approved no  
  Call Number CAT @ cat @ BVB2008 Serial 1004  
Permanent link to this record
 

 
Author T. Widemann; Xavier Otazu edit  doi
openurl 
  Title Titanias radius and an upper limit on its atmosphere from the September 8, 2001 stellar occultation Type Journal Article
  Year 2009 Publication International Journal of Solar System Studies Abbreviated Journal  
  Volume 199 Issue 2 Pages 458–476  
  Keywords Occultations; Uranus, satellites; Satellites, shapes; Satellites, dynamics; Ices; Satellites, atmospheres  
  Abstract On September 8, 2001 around 2 h UT, the largest uranian moon, Titania, occulted Hipparcos star 106829 (alias SAO 164538, a V=7.2, K0 III star). This was the first-ever observed occultation by this satellite, a rare event as Titania subtends only 0.11 arcsec on the sky. The star's unusual brightness allowed many observers, both amateurs or professionals, to monitor this unique event, providing fifty-seven occultations chords over three continents, all reported here. Selecting the best 27 occultation chords, and assuming a circular limb, we derive Titania's radius: View the MathML source (1-σ error bar). This implies a density of View the MathML source using the value View the MathML source derived by Taylor [Taylor, D.B., 1998. Astron. Astrophys. 330, 362–374]. We do not detect any significant difference between equatorial and polar radii, in the limit View the MathML source, in agreement with Voyager limb image retrieval during the 1986 flyby. Titania's offset with respect to the DE405 + URA027 (based on GUST86 theory) ephemeris is derived: ΔαTcos(δT)=−108±13 mas and ΔδT=−62±7 mas (ICRF J2000.0 system). Most of this offset is attributable to a Uranus' barycentric offset with respect to DE405, that we estimate to be: View the MathML source and ΔδU=−85±25 mas at the moment of occultation. This offset is confirmed by another Titania stellar occultation observed on August 1st, 2003, which provides an offset of ΔαTcos(δT)=−127±20 mas and ΔδT=−97±13 mas for the satellite. The combined ingress and egress data do not show any significant hint for atmospheric refraction, allowing us to set surface pressure limits at the level of 10–20 nbar. More specifically, we find an upper limit of 13 nbar (1-σ level) at 70 K and 17 nbar at 80 K, for a putative isothermal CO2 atmosphere. We also provide an upper limit of 8 nbar for a possible CH4 atmosphere, and 22 nbar for pure N2, again at the 1-σ level. We finally constrain the stellar size using the time-resolved star disappearance and reappearance at ingress and egress. We find an angular diameter of 0.54±0.03 mas (corresponding to View the MathML source projected at Titania). With a distance of 170±25 parsecs, this corresponds to a radius of 9.8±0.2 solar radii for HIP 106829, typical of a K0 III giant.  
  Address  
  Corporate Author Thesis  
  Publisher ELSEVIER Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0019-1035 ISBN Medium  
  Area (up) Expedition Conference  
  Notes CIC Approved no  
  Call Number CAT @ cat @ Wid2009 Serial 1052  
Permanent link to this record
 

 
Author Xavier Otazu; Maria Vanrell; C. Alejandro Parraga edit  openurl
  Title Colour induction effects are modelled by a low-level multiresolution wavelet framework Type Journal
  Year 2008 Publication Perception 37(Suppl.): 107 Abbreviated Journal  
  Volume Issue Pages  
  Keywords  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area (up) Expedition Conference  
  Notes CIC Approved no  
  Call Number CAT @ cat @ OVP2008b Serial 1055  
Permanent link to this record
 

 
Author C. Alejandro Parraga; Robert Benavente; Maria Vanrell; Ramon Baldrich edit  url
openurl 
  Title Psychophysical measurements to model inter-colour regions of colour-naming space Type Journal Article
  Year 2009 Publication Journal of Imaging Science and Technology Abbreviated Journal  
  Volume 53 Issue 3 Pages 031106 (8 pages)  
  Keywords image processing; Analysis  
  Abstract JCR Impact Factor 2009: 0.391
In this paper, we present a fuzzy-set of parametric functions which segment the CIE lab space into eleven regions which correspond to the group of common universal categories present in all evolved languages as identified by anthropologists and linguists. The set of functions is intended to model a color-name assignment task by humans and differs from other models in its emphasis on the inter-color boundary regions, which were explicitly measured by means of a psychophysics experiment. In our particular implementation, the CIE lab space was segmented into eleven color categories using a Triple Sigmoid as the fuzzy sets basis, whose parameters are included in this paper. The model’s parameters were adjusted according to the psychophysical results of a yes/no discrimination paradigm where observers had to choose (English) names for isoluminant colors belonging to regions in-between neighboring categories. These colors were presented on a calibrated CRT monitor (14-bit x 3 precision). The experimental results show that inter- color boundary regions are much less defined than expected and color samples other than those near the most representatives are needed to define the position and shape of boundaries between categories. The extended set of model parameters is given as a table.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area (up) Expedition Conference  
  Notes CIC Approved no  
  Call Number CAT @ cat @ PBV2009 Serial 1157  
Permanent link to this record
Select All    Deselect All
 |   | 
Details

Save Citations:
Export Records: