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Rotation Estimation: A Closed-Form Solution Using Spherical Moments

Hicham Hadj-Abdelkader, Omar Tahri, Houssem-Eddine Benseddik
2019 Sensors  
This paper uses spherical photometric moments for a closed form estimation of 3D rotations from images.  ...  Photometric moments are global descriptors of an image that can be used to recover motion information.  ...  Closed-Form Solution of Rotation Estimation From moments of order 1 and by using Equation (4), the interaction matrix that links time derivatives of the triple x m 1 = [m 100 m 010 m 001 ] to the rotational  ... 
doi:10.3390/s19224958 pmid:31739484 pmcid:PMC6891670 fatcat:7lyjjixuajefpanaqvn22q54ai

Mode Identification from Line Profiles Using the Direct Fitting Technique [chapter]

Luis A. Balona
2003 Asteroseismology Across the HR Diagram  
It is not restricted to low spherical harmonic degree or form of the eigenfunction and is not sensitive to the placement of the continuum.  ...  The direct fitting method has several advantages over the method of moments.  ...  The direct fitting technique has several advantages over the method of moments. Firstly, it is not limited to low values of or the particular form of the eigenfunction.  ... 
doi:10.1007/978-94-017-0799-2_16 fatcat:hm2b2lwl35falhgqy2yjskv76m

Adaptive Direct RGB-D Registration and Mapping for Large Motions [chapter]

Renato Martins, Eduardo Fernandez-Moral, Patrick Rives
2017 Lecture Notes in Computer Science  
The methodology is formulated for a generic warping model and results are given using perspective and spherical sensor models.  ...  The information gathered from the geometric and photometric cost functions is not only considered for improving the system observability, but for exploiting the different convergence properties and convexity  ...  The authors thank Josh Picard and Paolo Salaris for the discussions/proof reading of the manuscript, and the reviewers for their thoughtful comments.  ... 
doi:10.1007/978-3-319-54190-7_12 fatcat:gv33quoevzhptix4tivlfmir7q

Pulsational line profile variation of the roAp star HR 3831

O. Kochukhov
2006 Astronomy and Astrophysics  
Pulsational variation of the higher moments reveal substantial contribution of the high-order (ell=3) spherical harmonics which appear due to distortion of pulsations in HR 3831 by the global magnetic  ...  We interpret observations with a novel numerical model of the pulsational variation and rotational modulation of the line profile moments in roAp stars.  ...  for the surface geometry of pulsational perturbations departing from a pure spherical harmonic form.  ... 
doi:10.1051/0004-6361:20053345 fatcat:ba7cor53yrbslm63d6ikkgzyaa

Ear-to-ear Capture of Facial Intrinsics [article]

Alassane Seck, William A. P. Smith, Arnaud Dessein, Bernard Tiddeman, Hannah Dee, Abhishek Dutta
2016 arXiv   pre-print
Photometric measurements made in a lightstage are used to estimate view dependent high resolution normal maps.  ...  We use uncalibrated multiview stereo to estimate a coarse base mesh to which the photometric views are registered.  ...  ACKNOWLEDGMENTS We are grateful to Hadi Dahlan for assistance with data collection and to Fufu Fang for assistance with lightstage calibration and programming.  ... 
arXiv:1609.02368v1 fatcat:ir7aynfoybamjpmsfpszheux6m


Daniil Pavlenko
2013 Odessa Astronomical Publications  
of light scattering by the artificial satellite's surface), as well as provides examples of such solutions for simulated occurrences  ...  This article describes the method of determination of the Earth's artificial satellite's free (unplanned) rotation using its light curve and preliminary computed brightness charts (the spatial indicatrices  ...  Selection of certain three moments with the interval between them close to a ninth of the rotation period and readout of the observed brightness. 6.  ... 
doi:10.18524/1810-4215.2013.26.82272 doaj:0899c79b616b4b44968c7c136991f42a fatcat:lvsklegnvfb5xjknwezlc375dq

Analysis of theU B V light curves of TT hydrae by Kopal's frequency domain method

Jawahar Koul, K. D. Abhyankar
1982 Journal of astrophysics and astronomy  
Acknowledgement J.K. is thankful to University Grants Commission, New Delhi for the award of a Junior Research Fellowship.  ...  The A 2m s actually consist of three parts: (2) where A 2m are the moments for spherical stars, A2m include the proximity effects such as reflection and rotational-tidal distortion, and 2m are photometric  ...  Since the evolutionary status of undersized secondaries is controversial (Hall 1974) we have re-analysed the same data by Kopal's frequency domain technique which gives the solution in closed form.  ... 
doi:10.1007/bf02714793 fatcat:mmcolmalhrb5pmwqcrxta7zvse

Figure of the double Asteroid 90 Antiope from adaptive optics and lightcurve observations

P. Descamps, F. Marchis, T. Michalowski, F. Vachier, F. Colas, J. Berthier, M. Assafin, P.B. Dunckel, M. Polinska, W. Pych, D. Hestroffer, K.P.M. Miller (+8 others)
2007 Icarus (New York, N.Y. 1962)  
The combination of these complementary observations has enabled us to derive a reliable physical and orbital solution for the system.  ...  rotating bodies.  ...  For many purposes a Minnaert law can provide a useful approximation to the photometric properties of surfaces.  ... 
doi:10.1016/j.icarus.2006.10.030 fatcat:o4hyrmh4cnbbvpdk7gbnzj3efq

Line profile variations in Doradus

L. A. Balona, T. Bohm, B. H. Foing, K. K. Ghosh, E. Janot-Pacheco, K. Krisciunas, A.- M. Lagrange, W. A. Lawson, S. D. James, J. Baudrand, C. Catala, M. Dreux (+2 others)
1996 Monthly notices of the Royal Astronomical Society  
The only viable mechanism for understanding the variability is nonradial pulsation. We used the method of moments to identify the modes of pulsation of the three periodic components.  ...  We present data from high-dispersion echelle spectra and simultaneous uvby photometry for γ Doradus.  ...  Petterson for assistance with MIDAS reductions. WAL thanks Dr S James, ADFA, for computing support.  ... 
doi:10.1093/mnras/281.4.1315 fatcat:6m7vzl3gs5eo5lim4dr4p3lomq

Role of longitudinal activity complexes for solar and stellar dynamos

Maarit J. Mantere, Petri J. Käpylä, Jaan Pelt
2012 Proceedings of the International Astronomical Union  
We also present results from a pure α2 mean-field dynamo model, which show that time-dependent behavior of the dynamo solutions can occur both in the form of an azimuthal dynamo wave and/or oscillatory  ...  In this paper we first discuss observational evidence of longitudinal concentrations of magnetic activity in the Sun and rapidly rotating late-type stars with outer convective envelopes.  ...  MJM and PJK thank NORDITA for hospitality during their visits.  ... 
doi:10.1017/s1743921313002457 fatcat:s4sjpoih7nfe3buduiwcjrmmhy

Recovering the intrinsic shape of early-type galaxies

Remco C. E. van den Bosch, Glenn van de Ven
2009 Monthly notices of the Royal Astronomical Society  
For galaxies that are very round or show no significant rotation, recovery of the shape is degenerate, unless additional constraints such as from a thin disk are available.  ...  We simulate these observations with galaxy models that are representative of observed oblate fast-rotator to triaxial slow-rotator early-type galaxies.  ...  ACKNOWLEDGMENTS We thank Anne-Marie Weijmans and Tim de Zeeuw for useful comments on the manuscript, and Michele Cappelari for many lively discussions.  ... 
doi:10.1111/j.1365-2966.2009.15177.x fatcat:42yplctv75fmhpnvdxgwxxxsnu

Modeling of lightcurves of binary asteroids

P. Scheirich, P. Pravec
2009 Icarus (New York, N.Y. 1962)  
The pole solutions and size ratios for 1999 KW 4 and 2000 DP 107 are in a good agreement with independent estimates from radar measurements.  ...  We present a numerical method for inverting long-period components of lightcurves of asynchronous binary asteroids. 1998 RO 1 , for two of them from more than one apparition, were inverted.  ...  In modeling the long-period component of the lightcurve, a rotationally symmetric shape is used for the primary in order to flatten out its rotational component.  ... 
doi:10.1016/j.icarus.2008.12.001 fatcat:jkojjmf6ajeenihdybacli6nhu

Photometric mode identification methods of non-radial pulsations in eclipsing binaries - I. Dynamic eclipse mapping

I. B. Bíró, J. Nuspl
2011 Monthly notices of the Royal Astronomical Society  
The method needs a geometric model of the binary, accepts the light curve and the detected pulsation frequencies on input, and on output yields estimates of the pulsation patterns, in form of images --  ...  We conclude that, with reasonable assumptions, Dynamic Eclipse Mapping could be a powerful tool for mode identification, especially in moderately close eclipsing binary systems, where the pulsating component  ...  If the rotation axis is unknown, then only the assumption of smoothness can be used, leading to a 'smoothest' solution, which will for certain be inferior to the regular solution and may be insufficient  ... 
doi:10.1111/j.1365-2966.2011.18400.x fatcat:wo557icj2bgoxhu75s3ydyllgy

Measuring the Oblateness and Rotation of Transiting Extrasolar Giant Planets

Jason W. Barnes, Jonathan J. Fortney
2003 Astrophysical Journal  
We investigate the prospects for characterizing extrasolar giant planets by measuring planetary oblateness from transit photometry and inferring planetary rotational periods.  ...  However, the measured rotation rate for these objects is non-unique due to degeneracy between obliquity and oblateness and the unknown component of obliquity along the line of sight.  ...  There is no closed-form general analytical solution to the intersection of an ellipse and a circle.  ... 
doi:10.1086/373893 fatcat:7g3zwyysdfezthwcmzp3hxne3m

Shape Models and Physical Properties of Asteroids [chapter]

T. Santana-Ros, G. Dudziński, P. Bartczak
2016 Astrophysics and Space Science Proceedings  
Asteroids travelling in orbits that are potentially hazardous for the Earth form an especially interesting group to be studied.  ...  This paper briefly describes the data requirements and different techniques used to solve the lightcurve inversion problem.  ...  But the data improvement will be considerable, both in terms of quantity (observations are expected for ∼300.000 asteroids, [29] ) and quality (the photometric accuracy is estimated to be ∼0.01 mag for  ... 
doi:10.1007/978-3-319-46179-3_4 fatcat:nlu5a4pjnjhlfmi7jhxumjhspm
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