224 research outputs found
Toulouse Hyperspectral Data Set: a benchmark data set to assess semi-supervised spectral representation learning and pixel-wise classification techniques
Airborne hyperspectral images can be used to map the land cover in large
urban areas, thanks to their very high spatial and spectral resolutions on a
wide spectral domain. While the spectral dimension of hyperspectral images is
highly informative of the chemical composition of the land surface, the use of
state-of-the-art machine learning algorithms to map the land cover has been
dramatically limited by the availability of training data. To cope with the
scarcity of annotations, semi-supervised and self-supervised techniques have
lately raised a lot of interest in the community. Yet, the publicly available
hyperspectral data sets commonly used to benchmark machine learning models are
not totally suited to evaluate their generalization performances due to one or
several of the following properties: a limited geographical coverage (which
does not reflect the spectral diversity in metropolitan areas), a small number
of land cover classes and a lack of appropriate standard train / test splits
for semi-supervised and self-supervised learning. Therefore, we release in this
paper the Toulouse Hyperspectral Data Set that stands out from other data sets
in the above-mentioned respects in order to meet key issues in spectral
representation learning and classification over large-scale hyperspectral
images with very few labeled pixels. Besides, we discuss and experiment the
self-supervised task of Masked Autoencoders and establish a baseline for
pixel-wise classification based on a conventional autoencoder combined with a
Random Forest classifier achieving 82% overall accuracy and 74% F1 score. The
Toulouse Hyperspectral Data Set and our code are publicly available at
https://www.toulouse-hyperspectral-data-set.com and
https://www.github.com/Romain3Ch216/tlse-experiments, respectively.Comment: 17 pages, 13 figure
pVAE: a physics-integrated generative model. Application to the semantic segmentation of optical remote sensing images
The combination of machine learning models with physical models is a recent
research path to learn robust data representations. In this paper, we introduce
pVAE, a generative model that integrates a perfect physical model which
partially explains the true underlying factors of variation in the data. To
fully leverage our hybrid design, we propose a semi-supervised optimization
procedure and an inference scheme that comes along meaningful uncertainty
estimates. We apply pVAE to the semantic segmentation of high-resolution
hyperspectral remote sensing images. Our experiments on a simulated data set
demonstrated the benefits of our hybrid model against conventional machine
learning models in terms of extrapolation capabilities and interpretability. In
particular, we show that pVAE naturally has high disentanglement
capabilities. Our code and data have been made publicly available at
https://github.com/Romain3Ch216/p3VAE.Comment: 21 pages, 11 figures, submitted to the International Journal of
Computer Visio
Myths and lessons of liberal intervention: The British campaign for the abolition of the Atlantic slave trade to Brazil
This is the Pre-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2012 Martinus NijhoffThis article takes issue with recent references to the British nineteenth century campaign for the abolition of the trans-Atlantic slave trade to Brazil that serve to bolster interventionist or imperialist agendas. In particular, such accounts reproduce two and a half myths about the campaign: that it can serve as a model for the present age; that the success of the campaign can be explained through the actions of the intervening party alone (with a corresponding neglect of those of the ‘target’ state); and the half-myth that the campaign’s success was due to military action (at the expense of institutional (legal) and normative factors and the capacity of the target state). I argue instead that this case – and interventions more generally – would benefit from an analysis that considers the role of force in relation to a series of residual institutional and cultural constraints within the liberal state and to political conditions in the target state. In light of the complexities and contingencies that these factors present the underlying lesson is that military force should be used sparingly, if at all
A deeper look at the association between childhood maltreatment and reflective functioning
Childhood maltreatment is theorized as impeding the development of reflective functioning (RF; ability to perceive and interpret oneself and others in terms of mental states). However, previous research typically failed to support this association or yielded small sized and mixed associations. This study aims to provide a deeper look at the association between childhood maltreatment and RF by characterizing two non-mentalizing categories. One-hundred-and-sixteen pregnant women (mean age = 27.62, SD = 4.52) from the community (48.3% with a university degree, 96.5% in a relationship with the other parent) retrospectively reported on childhood abuse and neglect using the Childhood Trauma Questionnaire. They also participated in the Adult Attachment Interview subsequently coded using the Reflective Functioning Scale. Participants with poor to low RF were allocated to one of two groups (disavowal-distancing or distorted-inconsistent) using indicators provided in the RF Scale. No association was found between childhood maltreatment and overall RF when controlling for education level. A multinomial logistic regression revealed that childhood maltreatment was strongly predictive of a disrupted, over-analytical and inconsistent reflection about mental states but not of a tendency to discourse little about mental states. This tendency was rather only predicted by education level. Findings suggest that childhood maltreatment would lead to specific impairments in RF and that not considering how individuals fail to mentalize about attachment relationships may mask strong associations between RF and its determinants and correlates, including childhood maltreatment
Success in Developing Regions: World Records Evolution through a Geopolitical Prism
A previous analysis of World Records (WR) has revealed the potential limits of human physiology through athletes' personal commitment. The impact of political factors on sports has only been studied through Olympic medals and results. Here we studied 2876 WR from 63 nations in four summer disciplines. We propose three new indicators and show the impact of historical, geographical and economical factors on the regional WR evolution. The south-eastward path of weighted annual barycenter (i.e. the average of country coordinates weighting by the WR number) shows the emergence of East Africa and China in WR archives. Home WR ratio decreased from 79.9% before the second World War to 23.3% in 2008, underlining sports globalization. Annual Cumulative Proportions (ACP, i.e. the cumulative sum of the WR annual rate) highlight the regional rates of progression. For all regions, the mean slope of ACP during the Olympic era is 0.0101, with a maximum between 1950 and 1989 (0.0156). For European countries, this indicator reflects major historical events (slowdown for western countries after 1945, slowdown for eastern countries after 1990). Mean North-American ACP slope is 0.0029 over the century with an acceleration between 1950 and 1989 at 0.0046. Russia takes off in 1935 and slows down in 1988 (0.0038). For Eastern Europe, maximal progression is seen between 1970 and 1989 (0.0045). China starts in 1979 with a maximum between 1990 and 2008 (0.0021), while other regions have largely declined (mean ACP slope for all other countries = 0.0011). A similar trend is observed for the evolution of the 10 best performers. The national analysis of WR reveals a precise and quantifiable link between the sport performances of a country, its historical or geopolitical context, and its steps of development
CoMMA Corporate Memory Management through Agents Corporate Memory Management through Agents: The CoMMA project final report
This document is the final report of the CoMMA project. It gives an overview of the different search activities that have been achieved through the project. First, a description of the general requirements is proposed through the definition of two scenarios. Then it shows the different technical aspects of the projects and the solution that has been proposed and implemented
Entangling single photons on a beamsplitter
We report on a scheme for the creation of time-bin entangled states out of
two subsequent single photons. Both photons arrive on the same input port of a
beamsplitter and the situation in which the photons leave the beamsplitter on
different output ports is post-selected. We derive a full quantum mechanical
analysis of such time-bin entanglement for emitters subject to uncorrelated
dephasing processes and apply this model to sequential single photons emerging
from a single semiconductor quantum dot. Our results indicate that the
visibility of entanglement is degraded by decoherence effects in the quantum
dot, but can be restored by use of CQED effects, namely the Purcell effect.Comment: Accepted EPJ
Corporate Memory Management through Agents: The CoMMA project final report
This document is the final report of the CoMMA project. It gives an overview of the different search activities that have been achieved through the project. First, a description of the general requirements is proposed through the definition of two scenarios. Then it shows the different technical aspects of the projects and the solution that has been proposed and implemented
CC9 Livestock-Associated Staphylococcus aureus Emerges in Bloodstream Infections in French Patients Unconnected With Animal Farming
We report 4 bloodstream infections associated with CC9 agr type II Staphylococcus aureus in individuals without animal exposure. We demonstrate, by microarray analysis, the presence of egc cluster, fnbA, cap operon, lukS, set2, set12, splE, splD, sak, epiD, and can, genomic features associated with a high virulence potential in human
Transformations organisationnelles et devenir du rapport au travail (monographie du centre de tri postal de Nantes-Orvault)
NANTES-BU Lettres (441092102) / SudocSudocFranceF
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