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A search for OB stars in the field of the galactic OB association Bochum 7: II. Proper motion and IR photometry
(EDP Sciences, 2018-08)
Aims. We plan to identify the members of the Bochum 7 association by performing simultaneous astrometric and spectrophotometric analyses, and estimate its distance and evolutionary stage. Methods. We used our own visual ...
Self-propelled particles with fluctuating speed and direction of motion in two dimensions
(American Physical Society, 2007-12)
We study general aspects of active motion with fluctuations in the speed and the direction of motion in two dimensions. We consider the case in which fluctuations in the speed are not correlated to fluctuations in the ...
Measurement of Rate of Expansion in the Perception of Radial Motion
(Pergamon-Elsevier Science Ltd, 2005-12)
Optic flow generated by rigid surface patches can be decomposed into a small number of elementary motion types. In these experiments, we show that the human visual system can evaluate expansion, one of these motion types, ...
Signatures of homoclinic motion in quantum chaos
(American Physical Society, 2005-12)
Homoclinic motion plays a key role in the organization of classical chaos in Hamiltonian systems. In this Letter, we show that it also imprints a clear signature in the corresponding quantum spectra. By numerically studying ...
Speed adaptation as Kalman filtering
(Pergamon-Elsevier Science Ltd, 2008-10)
If the purpose of adaptation is to fit sensory systems to different environments, it may implement an optimization of the system. What the optimum is depends on the statistics of these environments. Therefore, the system ...
Features of the motion of gel particles in a three-phase bubble column under foaming and non-foaming conditions
(Chemical Industry Press, 2018-06)
Features of the motion of gel particles in a three-phase bubble column with non-foaming and foaming gas–liquid systems, determined by using experiments of radioactive particle tracking (RPT), have been compared. The tracer ...
Historic reconstruction of reservoir topography using contour line interpolation and Structure from Motion photogrammetry
(Taylor & Francis, 2018-09-05)
The geometry of impounded surfaces is a key tool to reservoir storage management and projection. Yet topographic data and bathymetric surveys of average-aged reservoirs may be absent for many regions worldwide. This paper ...
Computation of object approach by a system of visual motion-sensitive neurons in the crab Neohelice
(American Physiological Society, 2014-09)
.Similar to most visual animals, crabs perform proper avoidance responses to objects directly approaching them. The monostratified lobula giant neurons of type 1 (MLG1) of crabs constitute an ensemble of 14–16 bilateral ...
The effect of spatial layout on motion segmentation
(Pergamon-Elsevier Science Ltd, 2009-07)
We present a series of experiments exploring the effect of the stimulus spatial configuration on speed discrimination and two different types of segmentation, for random dot patterns. In the first experiment, we find that ...
New members of Cygnus OB2 from Gaia DR2
(Wiley Blackwell Publishing, Inc, 2021-04)
Due to the high quality of Gaia DR2 stellar parallaxes and proper motions, we can study the Cygnus OB2 region up to G = 17.5 mag in circular region centred at (l, b) = (79.8°, +0.8°) of radius 1°. We detect four overdensities ...