Pixelated Semantic Colorization

While many image colorization algorithms have recently shown the capability of producing plausible color versions from gray-scale photographs, they still suffer from limited semantic understanding. To address this shortcoming, we propose to exploit pixelated object semantics to guide image colorization. The rationale is that human beings perceive and distinguish colors based on the semantic categories of objects. Starting from an autoregressive model, we generate image color distributions, from which diverse colored results are sampled. We propose two ways to incorporate object semantics into the colorization model: through a pixelated semantic embedding and a pixelated semantic generator. Specifically, the proposed convolutional neural network includes two branches. One branch learns what the object is, while the other branch learns the object colors. The network jointly optimizes a color embedding loss, a semantic segmentation loss and a color generation loss, in an end-to-end fashion. Experiments on PASCAL VOC2012 and COCO-stuff reveal that our network, when trained with semantic segmentation labels, produces more realistic and finer results compared to the colorization state-of-the-art

Progressive vowel height harmony in Proto-Kikongo and Proto-Bantu

The systematic comparison of the different types of progressive Vowel Height Harmony (pVHH) attested within the Kikongo Language Cluster (KLC) leads to the conclusion that this common Bantu process of long-distance assimilation cannot be reconstructed to Proto-Kikongo. The ‘(a)symmetric-pVHH’ and ‘back-pVHH’ patterns, the two main and structurally different kinds of pVHH within the KLC, emerged independently and relatively late within two distinct subgroups, viz. South Kikongo and North Kikongo respectively. Moreover, the ‘(a)symmetric-pVHH’ pattern further spread from a South Kikongo focal area coinciding with the heartland of the Kongo kingdom to other parts of the KLC through contact-induced dialectal diffusion. Furthermore, the historical-comparative evidence from the KLC suggests that neither symmetric nor asymmetric pVHH should be reconstructed to Proto-Bantu, the most recent common ancestor of all Bantu languages

L'invention d'une nouvelle compétence : géomètre au XVIIIème siècle.

13 pagesLes éléments de mon analyse se situent dans un lieu classique de contrôle de l'invention technique, l'Académie Royale des sciences. Mais mon propos ici n'est pas de décrire la maturation d'un des multiples “fruit[s] de cet instinct de méchanique que la nature donne à certains hommes, indépendamment de la philosophie” Il s'agit plutôt de mettre en relation deux autres formes de l'invention, l'invention des “géomètres” du dix-huitième siècle et l'invention entendue au sens plus moderne de production originale, non seulement de savoir, mais aussi de pratiques et d'usages. Dans ce dernier sens, il s'agit de décrire les modes de constitution d'une “compétence” nouvelle, à savoir celle que développent les “géomètres” dans le domaine de l'astronomie et de la géodésie