GALLUCCIO , Laurent

Cet article propose de nouvelles approches de segmentation non supervisée. Nous proposons d'exploiter les propriétés d'une nouvelle mesure de distance reposant sur la construction d'arbres de recouvrement minimaux duaux: le Dual Rooted Prim Tree (DRooPi), pour construire une paire de classes candidates. Ces classes correspondent a une partition...

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This paper proposes an original approach to cluster multi-component data sets with an estimation of the number of clusters. From the construction of a minimal spanning tree with Prim's algorithm and the assumption that the vertices are approximately distributed according to a Poisson distribution, the number of clusters is estimated by...

In this paper, we introduce a new distance computed from the construction of dual-rooted minimal spanning trees (MSTs). This distance extends Grikschat's approach, exhibits attractive properties and allows to account for both local and global neighborhood information. Furthermore, a function measuring the probability that a point belongs to a...

An original approach to cluster multi-component data sets is proposed that includes an estimation of the number of clusters. Using Prim's algorithm to construct a minimal spanning tree (MST) we show that, under the assumption that the vertices are approximately distributed according to a spatial homogeneous Poisson process, the number of...

International audience

This paper introduces a novel distance measure for clustering high dimensional data based on the hitting time of two Minimal Spanning Trees (MST) grown sequentially from a pair of points by Prim's algorithm. When the proposed measure is used in conjunction with spectral clustering, we obtain a powerful clustering algorithm that is able to...

This paper introduces a novel distance measure for clustering high dimensional data based on the hitting time of two Minimal Spanning Trees (MST) grown sequentially from a pair of points by Prim's algorithm. When the proposed measure is used in conjunction with spectral clustering, we obtain a powerful clustering algorithm that is able to...

In 2021, the Gaia mission will release its third data set of measurements including for the first time thousands of reflectance spectra of asteroids. For the final release of Gaia, this number is expected to increase to 100 000. The reflectance spectra are derived from spectro-photometric detectors covering wavelengths from blue to red (from...

This paper focusses on a new clustering method called evidence accumulation clustering with dual rooted prim tree cuts (EAC-DC), based on the principle of cluster ensembles also known as ''combining multiple clustering methods". A simple weak clustering algorithm is introduced based upon the properties of dual rooted minimal spanning trees and...

This paper proposes an original approach to cluster multi-component data sets, including an estimation of the number of clusters. From the construction of a minimal spanning tree with Prim's algorithm, and the assumption that the vertices are approximately distributed according to a Poisson distribution, the number of clusters is estimated by...

Apart from producing a huge improvement in the determination of asteroid orbits, Gaia is also expected to trigger a revolution in the field of the determination of asteroid physical properties. This includes the determination of accurate values of the mass and bulk density for about 100 of the largest objects in the main belt; the determination...

Here we present the first Gaia spectroscopic observations of asteroids. These data will be used to identify the composition of asteroids. Gaia will obtain the largest spectroscopic survey of the Main asteroid Belt.

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Context. The Gaia mission of the European Space Agency is measuring reflectance spectra of a number of the order of 10 5 small solar system objects. A first sample will be published in the Gaia Data Release scheduled in 2021. Aims. The aim of our work was to test the procedure developed to obtain taxonomic classifications for asteroids based...

International audience

Context. Observational and instrumental difficulties observing small bodies below 0.5 μm make this wavelength range poorly studied compared with the visible and near-infrared. Furthermore, the suitability of many commonly used solar analogues, essential in the computation of asteroid reflectances, is usually assessed only in visible...